ui bulletin # 74 - gm upfitter · 2020. 6. 13. · f2 auto/f2 manual/f3 normal engine idle will...

The LG4 Isuzu 7.8L Duramax diesel engine offers additional PTO capabilities to those included withthe 6.6L diesel engine. These upfitter added features include remote PTO and throttle. Primaryconcerns to upfitters are:

1. The Medium Duty T-Series (Tilt Cab) has additional connectors to access these featurescompared to the C-Series, and

2. Programming is required to configure these enhanced capabilities. A TIS 2000 or a Tech 2 Programming Tool is required to make these changes. These tools are available at your GM dealer.

Notes:The LG4 is the only engine offered on the Medium Duty T-Series. References to the TAC motor andmodule in the Description & Programming sections refer to other engines. The Programming Guiderefers to configurations in the ECM and is not a �how to� guide for tool use. Referenced document ID#�s are GM service documents available to your GM dealer.

This Bulletin covers the following issues:

1. Basic PTO Description and Operation (document ID# 1212588)2. PTO Switch and Mounting3. Electrical Schematics4. Connector Pin-Outs and Locations5. Option Programming Guide (document ID# 1685008)

UI BULLETIN # 74SUBJECT: PTO Procedure for Tilt Cab Trucks

with (7.8L) LG4 Engine

MODELS AFFECTED: T-Series Medium Duty Truck (F6/F7/F8) (Chevrolet, GMC & Isuzu)

MODEL YEAR(S): 2005

DATE: 09/08/2005

REVISION DATE:

PAGE: 1 of 41

ADVISORY

TABLE OF CONTENTSPage # Description

3 Basic PTO Description and Operation (document ID# 1212588)4 � Modes of Operation4 � PTO � Preset Mode�Factory Default Setting4 � PTO � Preset Mode Function Table5 � PTO � Variable Mode5 � PTO � Variable Mode Function Table6 � Reprogramming the PCM/ECM for Fast Idle/PTO Using the Scan Tool9 PTO Switch and Mounting

10 Electrical Schematics10 � PTO Switch and Relay11 � Remote PTO and Throttle Connectors12 Connector Pin-Outs and Locations12 � Auto Cruise Switch/PTO Switch Diode13 � PTO Switch13 � PTO Relay14 � C103 Trans OPT � LCT Transmission15 � C103 Trans OPT � MD Transmission16 � C104 PTO Controls17 � C106 Remote PTO18 � C120 Remote Throttle19 � C106, C120, C103 Location20 � C104 Location21 � (LG4) Engine Control Module (ECM) � Connector C-123 � (LG4) Engine Control Module (ECM) � Connector C-225 Option Programming Guide (document ID# 1685008)25 � Stationary Preset PTO Mode25 � Factory Installed Hardware26 � Upfitter Installed Hardware29 � Stationary Variable PTO Mode29 � Factory Option30 � Upfitter Installed33 � Mobile Variable PTO Mode33 � Factory Option34 � Upfitter Installed36 � Fast Idle Mode37 � Cruise Control Options38 � Exhaust Brake Options39 � Vehicle Speed Limit Options39 � Gear Down Protection40 � Engine Idle Speed40 � High Idle Cold Engine Set Speed41 � Speed Axle Calibration

UI BULLETIN # 74 (cont.)

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1. Basic PTO Description and Operation (document ID# 1212588)POWER TAKE-OFF (PTO) DESCRIPTION AND OPERATION

Table 1: PTO � Preset Mode�Factory Default SettingTable 2: PTO � Preset Mode Function TableTable 3: PTO � Variable ModeTable 4: PTO � Variable Mode Function TableTable 5: Reprogramming the PCM/ECM for Fast Idle/PTO

The power take-off (PTO) is an upfitter integrated system that allows the user to create an auxiliarypower source that will drive either a hydraulic pump or a generator. When the operator requests PTOthe PTO switch will be turned ON and the engine RPM will go to a default standby speed. The PTOsolenoid will engage if all of the engage conditions are met. If any of the PTO engage conditions forthe specific operating mode are no longer valid, the engine controller will exit out of PTO mode.

The PTO system is integrated with the cruise control and engine control system. The PTO systemutilizes the following GM parts:

� The PTO enable switch� The cruise control multi-function switch� The PTO relay� The powertrain control module (PCM) with 8.1L gasoline only� The engine control module (ECM) with 6.6L or 7.8L diesel only� The throttle actuator control (TAC) module with 8.1L gasoline only� The TAC motor with 8.1L gasoline only

The following parts are upfitter supplied and installed:

� The load engage switch� The PTO solenoid

Voltage is supplied with the ignition switch in RUN and START through the engine 1 fuse to thesecondary side of the PTO relay and the PTO enable switch. When the PTO switch is turned ON,voltage will be present through the primary side of the PTO relay and at the PTO ON switch signalcircuit at the PCM. If the PCM sees all of the PTO engage conditions it will provide a ground for therelay. Current will flow through the coil in the PTO relay and close the normally open contacts. This will allow current to flow to the load engage switch. When the operator closes the load engage switchcurrent will flow to the PTO solenoid. If the PCM sees all of the PTO engage conditions the PCM willsend a class 2 signal to the TAC module. The TAC module will use the TAC motor to increase theengine RPM to the standby speed. In the event that any of the PTO requirements are no longer met then the PCM will return the engine RPM to idle and turn the PTO solenoid OFF.

For diesel applications, engine speed is controlled by the ECM and the fuel injection control module (FICM).


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Modes of Operation

PTO � Preset Mode�Factory Default Setting

The PTO preset mode is normally used for stationary applications. The PTO solenoid will remainengaged while mobile in the preset mode however PTO set and resume speed controls will beinoperative. The engine RPM will also return to normal. This mode provides a default standby speedthat varies depending on the engine and transmission combination. This mode also provides 2 defaultPTO control speeds. Please note that the standby speed is not to be used as a PTO control speed. Allvehicles that have the PTO option should be equipped with cruise control.

PTO � Preset Mode�Factory Default Setting TableProgrammable Factory Setting Minimum Value (RPM) Maximum Value (RPM)Parameters (RPM)

PTO Max 2200 L18-2100 L18-4200Engine Speed LB7/LG4-950 LB7/LG4-3100

F2 Auto/F2 Manual/F3Normal engine idle will override

PTO Standby RPM L18-800/850/1200 if higher than requested PTO 1300base idle

LB7-850/850

PTO Set Speed All/L18 Fam 3 PTO Set speed cannot be set L18/LB7,LC8,LG41250/1400 below PTO Standby speed 4200/3100

PTO Resume 1700 PTO Set Speed L18/LB7,LC8,LG4Speed 4200/3100

PTO � Preset Mode Function

The following chart shows how to toggle between the three PTO speeds through the SET andRESUME switches on the cruise control multifunction switch.

PTO � Preset Mode Function TablePresent PTO State Pressing Resulting PTO StatePTO Standby Speed SET PTO Set SpeedPTO Standby Speed RESUME PTO Resume Speed

PTO Set Speed SET PTO Standby SpeedPTO Set Speed RESUME PTO Resume Speed

PTO Resume Speed SET PTO Set SpeedPTO Resume Speed RESUME PTO Standby Speed


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PTO � Variable Mode

This PTO speed control mode is used for both stationary and mobile applications. This mode allowsPTO to be controlled in a fashion similar to cruise control. The operator is able to hold an engine RPM with the SET switch on the cruise stock. The operator can tap up to increase engine speed in100 RPM increments with the RESUME switch. The operator may also tap down to decrease enginespeed with the SET switch. Variable engine RPM may be obtained by holding either the SET orRESUME switch.

PTO � Variable Mode TableProgrammable Factory Setting Minimum Value (RPM) Maximum Value (RPM)Parameters (RPM)

PTO Max 2200 L18-2100 L18-4200Engine Speed LB7/LG4-950 LB7/LG4-3100

F2 Auto/F2 Manual/F3Normal engine idle will override

PTO Standby RPM L18-800/850/1200 if higher than requested PTO 1300base idle

LB7-850/850

PTO � Variable Mode Function TableSwitch Set Resume (w/Cruise Only)

Engine speed will decrease by 100 RPM Engine speed will increase by 100 RPM increments and will maintain new engine increments and will maintain new engine

Pressed Once speed value. Engine speed can be decreased speed value. Engine speed can be increased down to PTO Standby RPM speed value, all up to the PTO max engine speed value, all further SET inputs will be ignored further RESUME inputs will be ignored

Held Decelerates engine speed down to the PTO Increases engine speed up to the PTO max standby speed value engine speed value


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Reprogramming the PCM/ECM for Fast Idle/PTO Using the Scan Tool

The scan tool must be used to enable the Fast Idle and PTO options and adjust the factory presetparameters to the desired settings. The scan tool menu driven device is a hand held scan tool thatplugs into the datalink connector located underneath the dash near the driver�s seat. Once the scantool is connected, the following chart will guide the user.

Reprogramming the PCM/ECM for Fast Idle/PTOStep Current Menu Select

1 Main F0: Diagnostics2 Vehicle Identification Year of Vehicle3 Vehicle Identification Medium Duty Truck4 Vehicle Identification Make5 Vehicle Identification Series6 Powertrain Engine7 Powertrain Automatic or Manual8 Special Functions F3: PTO Options9 Current PTO Settings Change Options10 PTO Options Refer to the following information for the PTO options menu selections.

To Adjust the Mode of Operation:

The PTO options menu will appear with the selections:

� F0: Fast Idle� Preset PTO Speed Control� Variable PTO Speed Control

Once the mode of operation is selected the Current PTO Settings menu will appear with the adjustableparameters for the current mode.

This screen allows the user to increase or decrease engine RPM values using the INCREASE andDECREASE buttons. If the Engine Fault Shutdown feature is selected, the YES or NO Buttons willdetermine if this feature is enabled.

ImportantPlease be aware that UF3 and PTO high idle settings must be reprogrammed in the event that thePCM is replaced. It may be advisable to provide the PCM settings information to the customer in casethe PCM requires servicing during some point in the life of the vehicle.


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After all the settings are adjusted, the user will press the REPROGRAM button and the Current PTOSettings menu will appear with the changes. The ignition must be turned OFF for 10 seconds to ensurethat the program values are stored in the PCM.

PTO Components

PTO Switch

The PTO switch is mounted in the left side of the instrument panel. The PTO switch has two positions, ON and OFF. When the PTO switch is in the ON position, voltage will be present on the PTO ON switch signal circuit at the relay and the PCM. The PTO indicator is an LED and is integralwith the switch The indicator will illuminate when the switch is turned ON. The presence of the indicatorbeing on does not mean that the PTO solenoid is engaged. The cruise control multi-function switchmust be used in conjunction with the PTO switch. Illumination of the switch is provided through thedimming circuit.

Cruise Control Multi-Function Switch

Engine speed control of the PTO system must controlled by the function control switches located onthe multifunction turn signal lever. The cruise control function control switches includes the ON/OFF,SET/COAST, and RESUME/ACCEL. The switch assembly provides driver control of the PTO as well as the cruise control system. The SET/COAST and RESUME/ACCEL switches may be used toincrease and decrease engine RPM. See the chart above for recommended speeds.

PTO Relay

The PTO relay is located on the side of the underhood fuse block. Voltage is supplied with the ignitionswitch in RUN and START through the Engine 1 fuse to the secondary side of the PTO relay. The PTOswitch controls the voltage to the primary side of the PTO relay while the PCM controls the ground.

Load Engage Switch

The load engage switch is an upfitter supplied and installed part. The switch is remote. Voltage issupplied by the PTO relay to the normally open contacts of the switch. When the switch is closedcurrent will flow to the PTO solenoid.

PTO Solenoid

The solenoid is an upfitter supplied part and is replaceable on most PTOs. The PTO solenoid is used on clutch activated PTOs. The PTO relay supplies the solenoid with voltage when the relay is energized.


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PCM

The PCM is the control center of the PTO system. Applications with a 6.6L or 7.8L diesel use an ECM.The PCM monitors numerous engine and vehicle functions. To engage the PTO, the PCM must seethe following conditions:

� The engine must be running� The transmission must be in PARK or NEUTRAL� The park brake must be set for manual transmission only� The vehicle speed must be zero in Preset Mode only� The brake or clutch must not be depressed

The PCM constantly looks at the information from various sensors and other inputs, and controls thesystems that affect vehicle performance. The PCM also performs a diagnostic test on the electronicthrottle control system.

TAC Module

The TAC module is the control center for the electronic throttle system. The TAC module and the PCMcommunicate through a dedicated redundant serial data circuit. The TAC module and the PCM monitorthe commanded throttle position and compare the commanded position to the actual throttle position.This is accomplished by monitoring the APP and the throttle position (TP) sensor. These 2 values mustbe within a calibrated value of each other or a DTC may be set. The TAC module also monitors eachindividual circuit of the TP sensor and the APP to verify proper operation. The TAC module commandsthe TAC motor to increase or decrease the engine RPM.

TAC Motor

The TAC motor is part of the throttle body and controls the positions of the throttle. The motor is bi-directional and is controlled by the TAC module. The TAC motor increases or decreases the engine RPM.


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2. PTO Switch and MountingPOWER TAKE-OFF (PTO) COMPONENT VIEWS

T-Series Medium Duty Truck F6/F7/F8Instrument Panel Switches, Center Forward View

(1) Outside Heated Mirror Switch (DNN)(2) High Idle Switch (UF3) or Power Take-Off (PTO) Switch(3) Exhaust Brake Switch (K40)(4) Rear Axle Driver Control Switch � Two Speed (HPZ and Automatic Transmission)(5) Traction Control Switch (NW9)(6) Overdrive (OD) Defeat Switch (Allison® LCT)(7) Marker Lamp Switch (JE4, RQ2, and U86, or JE4, and RQ3)


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3. Electrical SchematicsPTO Switch and Relay


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Remote PTO and Throttle Connectors


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4. Connector Pin-Out and LocationPOWER TAKE-OFF (PTO) CONNECTOR END VIEWS

Table 1: Auto Cruise Switch/PTO Switch DiodeTable 2: PTO SwitchTable 3: PTO Relay

Auto Cruise Switch/PTO Switch Diode

Connector Part Information � 7323-9135-50� 3-Way F Yazaki (OG)

Pin Wire Color Circuit No. FunctionA GY DF49 Cruise Control On Switch SignalB L-GN/D-BU DF62 Cruise Control/PTO On Switch SignalC L-GN WB08 PTO On Switch Signal


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PTO Switch

Connector Part Information � 7323-5060-30� 6-Way F Yazaki (NA)

Pin Wire Color Circuit No. Function1 PK WB01 Ignition 1 Voltage2 L-GN WB02 PTO On Switch Signal3 L-GN WB03 PTO On Switch Signal4 BK WY01 Ground5 BK/RD WB04 Instrument Panel Lamps Dimming Control6 BK WY02 Ground

PTO Relay

Connector Part Information � 7323-6055-30� 5-Way Yazaki (BK)

Pin Wire Color Circuit No. Function30 PK WB08 Ignition 1 Voltage85 L-GN WB02 PTO On Switch � Signal86 PU WB05 PTO Control87 WH WB07 PTO Relay Output

87A � � Not Used


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INLINE HARNESS CONNECTOR END VIEWS

Document ID# 1468158 (Tables 3, 4, 5 & 7)2005 T-Series Medium Duty Truck F6/F7/F8

Table 3: C103 (Upfitter TRANS OPT Connector) Front Chassis Harness to Upfitter Supplied Harness (Allison® LCT Automatic Transmission)

Table 4: C103 (Upfitter TRANS OPT Connector) Front Chassis Harness to Upfitter Supplied Harness (Allison® MD Automatic Transmission)

Table 5: C104 (Upfitter PTO Connector) Front Chassis Harness to Upfitter Supplied PTO Controls Harness (PTO)

Table 7: C106 Front Chassis Harness to Upfitter Supplied Remote PTO Harness (PTO)

C103 (Upfitter TRANS OPT Connector) Front Chassis Harness to Upfitter Supplied Harness (Allison® LCT Automatic Transmission)

Connector Part � 12177081 Connector Part � 12052189� 10-Way F Metri-Pack 150 � 10-Way M Metri-Pack 150 Information Series, Sealed (BK) Information Series, Sealed (BK)

Pin Wire Color Circuit No. Function Pin Wire Color Circuit No. Function

A PU OA24 Engine Brake Enable A � � Upfitter UsageSignalB YE OA23 A/T Neutral Signal B � � Upfitter UsageC WH OA20 PTO Engaged Signal C � � Upfitter UsageD � � Not Used D � � Upfitter UsageE � � Not Used E � � Upfitter Usage

F BN OA21 Transmission Shift Inhibit F � � Upfitter UsageSignalG � � Not Used G � � Upfitter UsageH BK OA25 Low Reference H � � Upfitter UsageJ � � Not Used J � � Upfitter Usage

K D-BU OA26 Transmission Power K � � Upfitter UsageTake-Off Enable Signal


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C103 (Upfitter TRANS OPT Connector) Front Chassis Harness to Upfitter Supplied Harness (Allison® MD Automatic Transmission)

Connector Part � 12177081 Connector Part � 12052189� 10-Way F Metri-Pack 150 � 10-Way M Metri-Pack 150 Information Series, Sealed (BK) Information Series, Sealed (BK)


A PU NF52 Engine Brake Enable A � � Upfitter UsageSignalB YE NF53 A/T Neutral Signal B � � Upfitter UsageC WH NF62 PTO Enable Signal C � � Upfitter Usage

D YE NF51 Transmission Auxiliary D � � Upfitter UsageHold Signal

E GY NF50 Transmission Shift Inhibit E � � Upfitter UsageSignal

F BN NF48 Transmission Shift Inhibit F � � Upfitter UsageSignalG � � Not Used G � � Upfitter UsageH BK NF49 Low Reference H � � Upfitter UsageJ BK NF54 Low Reference J � � Upfitter UsageK � � Not Used K � � Upfitter Usage


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C104 (Upfitter PTO Connector) Front Chassis Harness to Upfitter Supplied PTO Controls Harness (PTO)

Connector Part � 12177081 Connector Part � 12052189� 10-Way F GT 150 Series, � 10-Way M Metri-Pack 150 Information Sealed (BK) Information Series, Sealed (BK)

Pin Wire Color Circuit No. Function Pin Wire Color Circuit No. FunctionA � � Not Used A � � Upfitter UsageB L-GN WB12 PTO Disable Signal B � � Upfitter UsageC WH WB07 PTO On Switch Signal C � � Upfitter UsageD BK WY03 Ground D � � Upfitter Usage

E-F � � Not Used E-F � � Upfitter UsageG D-BU/RD WB11 PTO Status Signal G � � Upfitter UsageH WH WB10 PTO Relay Output H � � Upfitter Usage

J-K � � Not Used J-K � � Upfitter Usage


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C106 Front Chassis Harness to Upfitter Supplied Remote PTO Harness (PTO)

Connector Part � 6195-0195 Connector Part � 6195-0201� 6-Way F Sumitomo,Information � 6-Way F Sumitomo, Sealed (BN) Information Sealed (BN)


A BK/YE DF05 PTO Set Switch Signal � A � � Upfitter UsageRemote

B WH/RD DF06 PTO Resume Switch B � � Upfitter UsageSignal � Remote

C D-GN/WH DF07 PTO Set Switch Signal C � � Upfitter UsageB � Remote

D RD/BK DF08 PTO Disable Switch D � � Upfitter UsageSignal � Remote

E BK/WH DF09 PTO Set Switch Signal E � � Upfitter UsageA � RemoteF BK CU05 Ground F � � Upfitter Usage


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C120 Front Chassis Harness to Upfitter PTO Throttle Position Sensor Harness (PTO)

Connector Part � 6189-0132 Connector Part � 6181-0073� 4-Way M Sumitomo,Information � 4-Way F Sumitomo, Sealed (D-GY) Information Sealed (D-GY)

Pin Wire Color Circuit No. Function Pin Wire Color Circuit No. Function1 L-BU/WH DF22 5-Volt Reference 1 � � Upfitter Usage2 L-BU/RD DF23 PTO Accel Switch Signal 2 � � Upfitter Usage3 L-BU/YE DF24 Low Reference 3 � � Upfitter Usage4 � � Not Used 4 � � Upfitter Usage


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DOCUMENT ID# 1552172 (FIGURE 1)

2005 T-Series Medium Duty Truck F6/F7/F8Inboard Left Frame Rail, Forward of #2 Crossmember

(1) Front Chassis Harness(2) C106 (6 Cavities � Upfitter Remote PTO Connector � PTO)(3) C120 (4 Cavities � Upfitter PTO Throttle Position Sensor Connector � PTO)(4) C100 (12 Cavities � Upfitter AUX WRG Connector)(5) C103 (10 Cavities � Upfitter TRANS OPT Connector � A/T)(6) Lower Left Frame Rail


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DOCUMENT ID# 1504632 (FIGURE 2)

2005 T-Series Medium Duty Truck F6/F7/F8Inboard Left Frame Rail, Rear of the Spring Perch

(1) Engine Bell Housing(2) C104 (10 cavities � Upfitter PTO Connector)(3) Front Chassis Harness(4) Left Frame Rail(5) Left Rear Spring Perch


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Engine Control Module (ECM) C-1

Connector Part Information:� 1928404781� 96-Way F Bosch (BK)


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Pin Wire Circuit FunctionColor No.1 BK CU15 Ground2 BK CU09 Ground3 BK CU10 Ground4 BK CU13 Ground5 BK CU14 Ground6 � � Not Used7 TN CF13 Low Reference8 VT CF16 Low Reference9 RD CF19 Low Reference10 L-BU/YE DF24 Low Reference11 � � Not Used12 BK/YE CF96 Low Reference13 � � Not Used

14GY OA19 Ground (Allison® LCT)

BK/YE DF41 Drain Wire (M/T)15 � � Not Used16 TN CF10 Shield17 WH/RD CF36 SAE J1939 Serial Data Bus+18 L-GN/RD CF37 SAE J1939 Serial Data Bus�19 � � Not Used20 D-GN CF34 ECM Class 2 Serial Data A21 � � Not Used22 PK DF55 Ignition 0 Voltage

Pin Wire Circuit FunctionColor No.23 PK CF10 Ignition 1 Voltage

24-25 � � Not Used26 BK CU11 Ground27 BK CU12 Ground28 WH CF22 Engine Speed Signal

29-30 � � Not Used31 L-BU CF12 APP Sensor 1 Signal32 L-GN CF15 APP Sensor 2 Signal33 D-GN CF18 APP Sensor 3 Signal34 L-BU/RD DF22 PTO Accel Switch Signal

35-36 � � Not Used37 VT CF97 Fuel Level Signal � Primary38 L-BU CF99 Fuel Level Signal � Secondary

WH OA16 VSS High Signal (Allison® LCT)39 WH DF38 Signal High � Rear (Manual Trans.)

� � Not Used (Allison® MD)

40BK DF39 Signal Low � Rear (Manual Trans.)� � Not Used (Automatic Trans.)

41 RD/BK DF59 Generator Field Duty Cycle Signal42 � � Not Used

43 RD/D-BU DF56 Shift Motor Relay � Control (HPZ)� � Not Used (w/o HPZ)

44-45 � � Not Used(continued on next page)

Engine Control Module (ECM) C-1 � (continued)


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Pin Wire Circuit FunctionColor No.46 RD/BK DF50 Cruise Control On Switch Signal

47 RD DF48 Cruise Control Resume/AccelSwitch Signal

48 L-BU DF47 Cruise Control Set/Coast SwitchSignal

49 BK CF04 Ignition 1 Voltage50 BK/RD CF05 Ignition 1 Voltage51 L-BU/OG CF08 Battery Positive Voltage52 WH CF06 ECM Power Enable Signal53 WH CF07 ECM Power Enable Signal54 WH/BK CF11 5-Volt Reference55 BK/WH CF14 5-Volt Reference56 YE/BK CF17 5-Volt Reference57 � � Not Used58 L-BU/WH DF22 5-Volt Reference

59-60 � � Not Used61 RD DF60 Charge Indicator Control

62WH DF43 Stop Lamp Switch Signal (JE3)WH DF46 Stop Lamp Switch Signal (JE4)

63 RD/D-BU DF45TCC Brake Switch/Cruise ControlRelease Signal

64BK/OG CF29 CPP Switch Signal (Manual Trans.)

� � Not Used (Automatic Trans.)65-66 � � Not Used

67 WH CF32 Exhaust Brake Request Signal68 D-GN CF24 High Idle Switch Signal69 � � Not Used

Pin Wire Circuit FunctionColor No.70 L-GN DF61 Coolant Level Switch Signal71 L-GN BA03 Backup Lamp Supply Voltage

72-73 � � Not Used74 YE HB04 Glow Plug Relay Control75 VT WB05 PTO Control76 YE DF58 Starter Relay Coil Control77 VT DF44 Exhaust Brake Relay Control78 RD CF26 High Idle Indicator Control79 L-BU CF21 Wait to Start Indicator Control80 BK/WH CF20 MIL Control81 D-GN/WH CF23 Vehicle Speed Signal82 WH/BK DF57 Vehicle Speed Signal

83-85 � � Not Used

86 WH/BK DF01Brake/Clutch Switch OverrideSignal

87 � � Not Used88 RD/BK DF02 PTO Disable Switch Signal � Cab89 BK/WH DF04 PTO Set Switch Signal A90 D-GN/WH DF03 PTO Set Switch Signal B91 BK/YE DF05 PTO Set Switch Signal � Remote

92 WH/RD DF06PTO Resume Switch Signal �Remote

93 L-GN WB09 PTO On Switch Signal94 L-GN WB12 PTO Engine Kill Signal95 L-BU/RD WB11 PTO Engage Signal96 YE CF35 PNP/Clutch Start Switch Signal

Engine Control Module (ECM) C-2

Connector Part Information:� 1928404751� 58-Way F Bosch (BK)


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Pin Wire Circuit FunctionColor No.Turbocharger Vane Position

1 BK B1 Control Solenoid Valve HighControl

2 � � Not Used3 WH B3 Injector Positive Voltage Control 14 RD B4 Injector Positive Voltage Control 25 WH B5 Injector Positive Voltage Control 16 RD B6 Injector Positive Voltage Control 27 BK/WH B7 EGR Motor U Supply Voltage8 L-GN B8 EGR Motor V Supply Voltage9 RD/YE B9 EGR Motor W Supply Voltage10 � � Not Used11 BK B11 Not Used12 BK B12A Low Reference13 BK B13A Low Reference14 BK/YE B14 Low Reference15 GY B15A Low Reference16 BK B16A Low Reference17 WH/BK B17 Ground18 BK B18A Drain Wire19 GY B19 Drain Wire20 RD B20 SCV Low Signal21 RD B21 SCV Low Signal

Pin Wire Circuit FunctionColor No.22 � � Not Used23 RD B23 Not Used24 WH B24 MAP Sensor Signal25 WH B25A Fuel Pressure Sensor Signal26 WH B26 Fuel Pressure Sensor Signal27 GY B27 Oil Pressure Sensor Signal28 WH B28 MAF Sensor Signal29 WH B29 Turbocharger Vane Position Signal30 WH B30 CMP Sensor Low31 WH B31 CKP Sensor High32 BK B32 CKP Sensor Low33 WH B33 SCV High Signal34 WH B34 SCV High Signal35 D-BU/WH B35 ECT Sensor Signal36 � � Not Used37 L-GN/WH B37 IAT Sensor Signal38 D-BU/RD B38 EGR Motor Position U Signal39 WH/RD B39 EGR Motor Position V Signal40 YE/RD B40 EGR Motor Position W Signal41 YE B41 Fuel Temperature Sensor Signal42 RD B42 Low Reference43 RD B43 Fuel Injector 6 Control

(continued on next page)

Engine Control Module (ECM) C-2 � (continued)


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Pin Wire Circuit FunctionColor No.44 BK B44 Fuel Injector 4 Control44 BK B44 Fuel Injector 4 Control45 BK/RD B45 Fuel Injector 5 Control46 RD B46 5-Volt Reference47 RD B47 5-Volt Reference48 WH B48 5-Volt Reference49 WH B49 5-Volt Reference

Pin Wire Circuit FunctionColor No.50 RD B50 5-Volt Reference51 RD B51 5-Volt Reference52 L-GN B52 Oil Level Switch Signal

53-55 � � Not Used56 WH B56 Fuel Injector 3 Control57 L-BU B57 Fuel Injector 2 Control58 YE B58 Fuel Injector 1 Control

5. Option Programming Guide (document ID# 1685008)OPTION PROGRAMMING

Power Take-Off (PTO) System

PTO Option Programming

The PTO Option Programming must be done when any of the following procedures are performed:� When the upfitter installs a PTO system� When the ECM is replaced� When a change of the PTO setting is needed

PTO Control System Description

Refer to Power Take-Off (PTO) Description and Operation.

Stationary Preset PTO Mode

Important: If the engine speed the driver requests by pressing on the accelerator pedal is higher thanthe PTO desired engine speed, the accelerator pedal engine speed is used.

In Stationary Preset PTO mode, the PTO control is performed while the vehicle is stopped by arbitrarilyselecting one of multiple preset, up to four not including PTO base idle speed, engine speeds as thePTO desired engine speed.

Hardware Configuration � Factory Installed

PTO Switch

Important: The PTO base idle speed can change within the following allowable range:� Minimum � 600 RPM� Maximum � 1200 RPM� Preset value � 1000 RPM

Important: The PTO maximum engine speed can change within the following allowable range:� Minimum � 1000 RPM� Maximum � 2550 RPM� Preset value � 2400 RPM

The factory-option dash mounted PTO switch is used to enable or cancel the PTO mode. The enginespeed will be set to the PTO base idle speed when the PTO switch is pressed. The switch is a push-lock type switch. The input circuit is connected to the ECM 93 of C-1 connector.


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Cruise Set/Coast Switch

Important: The PTO Set speed can change within the following allowable range:� Minimum � PTO Base Idle Speed� Maximum � PTO Maximum Engine Speed� Preset value � 1400 RPM

Important:� The PTO Set speed cannot be higher than the PTO Resume speed.

� The PTO Resume speed cannot be higher than the PTO Maximum Engine speed.

The factory-installed combination switch mounted Cruise Set/Coast switch can be used in PTO modeto set the PTO Set speed, one fixed engine speed, when this switch is pressed. The switch is amomentary switch. The input circuit is connected to the ECM 48 of C-1 connector.

Cruise Resume/Accel. Switch

Important: The PTO Resume Speed can change within the following allowable range:� Minimum � PTO Base Idle Speed� Maximum � PTO Maximum Engine Speed� Preset value � 1700 RPM

Important:� The PTO Resume Speed cannot be lower than the PTO Set Speed.

� The PTO Resume Speed cannot be higher than the PTO Maximum Engine Speed.

The factory-installed combination switch mounted Cruise Resume/Accel. switch can be used in PTOmode to set the PTO Resume Speed, another fixed engine speed, when this switch is operated. Theswitch is a momentary switch. The input circuit is connected to the ECM 47 of C-1 connector.

Hardware Configuration � Upfitter Installed

Remote PTO Set Switch

Important:� The Remote PTO Set switch engine speed uses the PTO Set Speed value.

� The Remote PTO Set switch must be enabled, programmed, in the ECM.

The upfitter-installed Remote PTO Set switch can be used in PTO mode to set the Remote PTO Setswitch, the same engine speed as the PTO Set Speed, when this switch is pressed. The function ofthis switch is the same as the Cruise Set/Coast switch in the cab. The switch needs to be a momentaryswitch. The upfitter PTO connector is equipped with an input circuit to the ECM 91 of C-1 connectorthrough the A of C106 connector.


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Remote PTO Resume Switch

Important:� The Remote PTO Set switch engine speed uses the PTO Resume Speed value.


The upfitter-installed Remote PTO Resume switch can be used in PTO mode to set the Remote PTOResume switch, the same engine speed as the PTO Resume Speed, when this switch is pressed. Thefunction of this switch is the same as the Cruise Resume/Accel. switch in the cab. The switch needs tobe a momentary switch. The upfitter PTO connector is equipped with an input circuit to the ECM 92 ofC-1 connector through the B of C106 connector.

Remote Set Speed A Switch

Important: The Remote Set Speed A/B switches engine speed can change within the followingallowable range:

� Minimum � PTO base idle speed� Maximum � PTO maximum engine speed� Preset value � 1400 RPM

Important: The Remote Set Speed A switch must be enabled, programmed, in the ECM.

The upfitter-installed Remote Set Speed A switch can be used in PTO mode to set the PTO Set Speed A when this switch is pressed. The switch needs to be a momentary switch. The upfitter PTO connector is equipped with an input circuit to the ECM 89 of C-1 connector through the D ofC106 connector.

Remote Set Speed B Switch

Important: The Remote Set Speed A/B switches engine speed can change within the followingallowable range:

� Minimum � PTO base idle speed� Maximum � PTO maximum engine speed� Preset value � 1700 RPM

Important: The Remote Set Speed B switch must be enabled, programmed, in the ECM.

The upfitter-installed Remote Set Speed B switch can be used in PTO mode to set the PTO Set Speed B when this switch is pressed. The switch needs to be a momentary switch. The upfitter PTOconnector equipped with an input circuit to the ECM 90 of C-1 connector through C of C209 connector.


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PTO Engage Relay

Important: The PTO Engage Relay turn ON, ECM grounding coil control circuit, engine speed canchange within the following allowable range:

� Minimum � PTO Base Idle Speed� Maximum � PTO Maximum Engine Speed� Preset value � 1050 RPM

Important:� The PTO Engage Relay turn ON engine speed cannot be higher than any PTO speed except

the PTO base idle speed.

� The PTO Engage Relay must be enabled and programmed in the ECM.

The upfitter-installed PTO Enable Relay can be used to supply switched battery voltage to operate aPTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay iscontrolled via the ECM grounding the relay coil control circuit. The input circuit is connected to theECM 75 of C-1 connector.

PTO Feedback Switch

Important: PTO Feedback input to the ECM can be set via ECM programming. The preset is No or Disabled.

Some applications require that the operator press an upfitter installed momentary switch, usuallylocated outside the cab, before entering any PTO set speed, not PTO base idle speed. The switch isnormally tied into the PTO Engage Relay switch circuit. Once the switch is pressed with the relayturned ON, the ECM should detect a high voltage at the PTO Feedback switch input. This momentarilyhigh input will allow the operator to use any of the PTO speeds above the PTO base idle speed untilthe PTO mode is cancelled. The upfitter PTO connector is equipped with an input circuit to the ECM 95of C-1 connector through G of C104 connector.

PTO Engine Shutdown Switch

Important: The time preceding the engine shutdown once the input has been received can be setwithin the following allowable range for: PTO Engine Shutdown Time Delay:

� Minimum � 0 seconds� Maximum � 255 seconds� Preset value � 0 seconds

Important: The PTO Engine Shutdown must be enabled, programmed, in the ECM, AND the ECMmust detect a low voltage input at pin 94 of C-1 connector. These are both necessary for this shutdownfeature to operate.

The upfitter-installed PTO Engine Shutdown switch can be used in PTO mode to turn Off the engine.The switch needs to be a momentary switch. The upfitter PTO connector equipped with an input circuitto the ECM 94 of C-1 connector through the B of C104 connector.


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Stationary Variable PTO Mode

Important: In Stationary Variable PTO mode, the PTO control is performed while the vehicle isstopped by arbitrarily selecting engine speed as the PTO desired engine speed.

Hardware Configuration

The Stationary Variable PTO mode is enabled based on the following hardware inputs to the ECM:

Factory-option

PTO Switch

Important: The PTO Base Idle Speed can change within the following allowable range:� Minimum � 600 RPM� Maximum � 1200 RPM� Preset value � 1000 RPM

Important: The PTO Maximum Engine Speed can change within the following allowable range:� Minimum � 1000 RPM� Maximum � 2550 RPM� Preset value � 2400 RPM

The factory-option dash mounted PTO Switch is used to enable or cancel PTO mode. The enginespeed will be set to the PTO base idle speed when the PTO switch is pressed. The switch is a push-lock type switch. The input circuit is connected to the ECM 93 of C-1 connector.


Important: The PTO Decreased RPM Rate, decrement by a pressing, can change within the followingallowable range:

� Minimum � 0 RPM� Maximum � 1000 RPM� Preset value � 25 RPM

The factory-installed combination switch mounted Cruise Set/Coast Switch can be used in PTO modeto decrease the engine speed when this switch is tapped or while this switch is pressed. The switch isa momentary switch. The input circuit is connected to the ECM 48 of C-1 connector.


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Important: The PTO Resume/Accel. Switch Increase RPM rate, increment by a tapping, uses the PTOIncrease RPM Rate value. The PTO Increase RPM Rate, increment by a pressing, can change withinthe following allowable range:


The factory-installed combination switch mounted Cruise Resume/Accel. Switch can be used in PTOmode to increase the engine speed when this switch is tapped or while this switch is operating. Theswitch is a momentary switch. The input circuit is connected to the ECM 47 of C-1 connector.

Upfitter-installed

Remote PTO Set Switch

Important:� The Remote PTO Set switch Decrease RPM rate, decrement by a tapping, uses the PTO

Decrease RPM Rate value.


The upfitter-installed Remote PTO Set switch can be used in PTO mode to decrease the engine speed when this switch is tapped or while this switch is pressed. The function of this switch is same as the Cruise Set/Coast switch in the cab. The switch needs to be a momentary switch. The upfitterPTO connector equipped with an input circuit to the ECM 91 of C-1 connector through the A of C106 connector.

Remote PTO Resume Switch

Important:� The Remote PTO Resume switch Increase RPM rate, increment by a tapping, uses the PTO

Increase RPM Rate value.

� The Remote PTO Resume switch increase ramp rate, increment by a pressing, uses the PTOIncrease Ramp RPM Rate value.

� The Remote PTO Resume switch must be enabled, programmed, in the ECM.

The upfitter-installed Remote PTO Resume switch can be used in PTO mode to increase the engine speed hen this switch is tapped or while this switch is pressed. The function of this switch issame as the Cruise Resume/Accel. switch in the cab. The switch needs to be a momentary switch.The upfitter PTO connector equipped with an input circuit to the ECM 92 of C-1 connector through the B of C106 connector.


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Remote PTO Accelerator Sensor

Important:� The PTO engine speed control range by the sensor can control within the following

allowable range:� Minimum � PTO Base Idle Speed� Maximum � Remote PTO Throttle Maximum Engine Speed� Preset value � 1000 RPM

� It is necessary to program the Remote PTO Accelerator Sensor signal volume inputs to theECM at position 0 percent and 100 percent.� Preset value at 0 percent: 1 volts� Preset value at 100 percent: 4 volts

� If the ECM detects that the Remote PTO Throttle sensor signal is more than 4.9 volts, DTCP2005 will set.

� The Remote PTO Throttle Sensor must be enabled, programmed, in the ECM.

The upfitter-installed Remote PTO Accelerator sensor can be used in PTO mode to increase ordecrease the engine speed while this sensor is operating. The sensor needs to be a potentiometer.The ECM supplies 5 volts reference circuit to the Remote PTO throttle sensor from the ECM 58 of C-1connector through the 1 of C120 connector. The ECM also provides a ground on the low referencecircuit from the ECM 10 of C-1 connector through the 3 of C120 connector. The ECM monitors thesensor signal on the ECM 34 of JC-1 connector through the 2 of C120 connector.

PTO Engage Relay

Important:� The PTO Enable Relay turn ON, ECM grounding coil control circuit, engine speed can change

within the following allowable range:� Minimum � PTO Base Idle Speed� Maximum � PTO Maximum Engine Speed� Preset value � 1050 RPM

� The PTO Engage Relay turn ON engine speed cannot be higher than any PTO speed exceptthe PTO base idle speed.

� The PTO Engage Relay must be enabled and programmed in the ECM.

The upfitter-installed PTO Engage Relay can be used to supply switched battery voltage to operate aPTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay iscontrolled via the ECM grounding the relay coil control circuit. The input circuit is connected to theECM 75 of C-1 connector.


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PTO Feedback Switch

Important: PTO Feedback input to the ECM can be set via ECM programming. The preset is No orDisabled.

Some applications require that the operator press an upfitter installed momentary switch usuallylocated outside the cab before entering any PTO set speed, not PTO Base Idle Speed. The switch isnormally tied into the PTO Engage Relay switch circuit. Once the switch is pressed with the relayturned ON, the ECM should detect a high voltage at the PTO Feedback Switch input. This momentarilyhigh input will allow the operator to use any of the PTO speeds above the PTO Base Idle Speed untilPTO mode is cancelled. The upfitter PTO connector is equipped with an input circuit to the ECM 95 of C-1 connector through G of C104 connector.


Important:� The time preceding the engine shutdown once the input has been received can be set within

the following allowable range: PTO Engine Shutdown Time Delay:� Minimum � 0 seconds� Maximum � 255 seconds� Preset value � 0 seconds

� PTO Engine Shutdown must be enabled, programmed, in the ECM, AND the ECM mustdetect a low voltage input at pin 94 of C-1 connector. These both are necessary for thisshutdown feature to operate.

The upfitter-installed PTO Engine Shutdown switch can be used in PTO mode to turn OFF the engine.The switch needs to be a momentary switch. The upfitter PTO connector equipped with an input circuitto the ECM 94 of C-1 connector through the B of C104 connector.


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Mobile Variable PTO Mode

Important:� If the engine speed the driver requests by pressing on the accelerator pedal is higher than the

PTO desired engine speed, the accelerator pedal engine speed is used.

� The PTO Maximum Vehicle Speed for Mobile Variable PTO mode can change within thefollowing allowable range:� Minimum � 0 km/h (0 mph)� Maximum � 113 km/h (70 mph)� Preset value � 40 km/h (25 mph)

� When a Maximum Vehicle Speed value is set, the vehicle will not exceed this value in PTOmode, even if the PTO Maximum Vehicle Speed is higher.

In Mobile Variable PTO mode, the PTO control is performed while the vehicle is running by arbitrarilyselecting engine speeds as the PTO desired engine speed. The system allows increases or decreasesthe PTO base idle speed by two switch inputs into the ECM while the vehicle is running.


Mobile Variable mode uses only switches in the cab, and is enabled based on the following hardwareinputs to the ECM:

Factory-option

PTO Switch

Important:� The PTO base idle speed can change within the following allowable range:


� The PTO maximum engine speed can change within the following allowable range:� Minimum � 1000 RPM� Maximum � 2550 RPM� Preset value � 2400 RPM

The factory-option dash mounted PTO switch is used to enable or cancel the PTO mode. The enginespeed will be set to the PTO base idle speed when the PTO switch is pressed. The switch is a push-lock type switch. The input circuit is connected to the ECM 93 of C-1 connector.


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Important: The PTO Decrease RPM Ramp Rate, decrement by a pressing, can change within thefollowing allowable range:


The factory-installed combination switch mounted Cruise Set/Coast switch can be used in PTO modeto decrease the engine speed when this switch is tapped or while this switch is pressing. The switch isa momentary switch. The input circuit is connected to the ECM 48 of C-1 connector.


Important:� The PTO Resume/Accel. switch increase RPM rate, decrement by a tapping, uses the PTO

Tap Bump Rate value.

� The PTO Increase Ramp RPM Rate, increment by a pressing, can change within the followingallowable range:� Minimum � 0 RPM� Maximum � 1000 RPM� Preset value � 25 RPM

The factory-installed combination switch mounted Cruise Resume/Accel. switch can be used in PTOmode to increase the engine speed when this switch is tapped or while this switch is pressed. Theswitch is a momentary switch. The input circuit is connected to the ECM 47 of C-1 connector.

Upfitter-installed

PTO Engage Relay

Important:� The PTO Engage Relay turn ON, ECM, grounding coil control circuit, engine speed can

change within the following allowable range:� Minimum � PTO Base Idle Speed� Maximum � PTO Maximum Idle Speed� Preset value � 1050 RPM

� The PTO Engage Relay turn ON engine speed cannot be higher than any PTO speed exceptthe PTO base idle speed.

The upfitter-installed PTO Engage Relay can be used to supply switched battery voltage to operate aPTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay iscontrolled via the ECM grounding the relay coil control circuit. The input circuit is connected to theECM 75 of C-1 connector.


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PTO Feedback Switch

Important: PTO Feedback input to the ECM can be set via ECM programming. The preset is No or Disabled.

Some applications require that the operator press an upfitter installed momentary switch, usuallylocated outside the cab, before entering any PTO set speed, not PTO base idle speed. The switch is normally tied into the PTO Engage Relay switch circuit. Once the switch is pressed with the relayturned ON, the ECM should detect a high voltage at the PTO Feedback switch input. This momentarilyhigh input will allow the operator to use any of the PTO speeds above the PTO base idle speed untilthe PTO mode is cancelled. The upfitter PTO connector is equipped with a voltage feed circuit to thePTO Engage Relay. Also, the upfitter PTO connector is equipped with an input circuit to the ECM 95 of C-1 connector through G of C104 connector.


Important:� The vehicle speed preceding the Engine Shutdown Time Delay once input has been received

must be 0 km/h (0 mph) or the engine will not shut down.

� The time preceding the engine shutdown once the input has been received can be set withinthe following allowable range:

� PTO Engine Shutdown Time Delay:� Minimum � 0 seconds� Maximum � 255 seconds� Preset value � 0 seconds

� PTO Engine Shutdown must be enabled, programmed, in the ECM AND the ECM must detecta low voltage input at pin 94 of C-1 connector. These both are necessary for this shutdownfeature to operate.

The upfitter-installed PTO Engine Shutdown Switch can be used in PTO mode to turn Off the engine.The switch needs to be a momentary switch. The upfitter PTO connector equipped with an input circuitto the ECM 94 of C-1 connector through the B of C104 connector.


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Fast Idle Mode

In Fast Idle mode, the engine idle speed control is performed while the vehicle is stopped by turning onthe high idle switch. There is only one preset engine speed for the function. Also, the ECM will onlyallow one of the following to be enabled at a time:

� Fast Idle Mode� Stationary Preset PTO Mode� Stationary Variable PTO Mode� Mobile Variable PTO Mode


The Fast Idle mode is enabled based on the following hardware inputs to the ECM:

Factory-option

High Idle Switch

Important:� The Fast Idle Set Speed can change within the following allowable range:


� The Fast Idle function must be enabled, programmed, in the ECM.

� The PTO modes are disabled in the ECM when Fast Idle mode is enabled.

The factory-installed option dash mounted High Idle switch can be used in Fast Idle mode to enablethe Fast Idle Set Speed, one fixed engine speed, when this switch is pressed. The switch is amomentary switch. The input circuit is connected to the ECM 68 of C-1 connector.


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Cruise Control System

Cruise Control Options Programming

The Cruise Control Option Programming must be done when any of the following procedures are performed:

� When the ECM is replaced� When change of the minimum cruise control speed is needed� When change of the maximum cruise control speed is needed� When the exhaust brake control assist is needed in cruise control

The operational speed range of the cruise control system can be changed within the followingallowable range:

� Minimum � 30 km/h (19 mph)� Maximum � 120 km/h (75 mph)

The cruise control system can be programmed to utilize the exhaust brake to help maintain vehiclespeed. The ECM default for this option is set to No.

This exhaust brake assist in cruise control is enabled when the following conditions are met:� The exhaust brake in cruise mode is programmed.� The exhaust brake request switch is ON.� Cruise control mode is active.� The accelerator pedal is not pressed.� The actual vehicle speed is higher than the Cruise set speed.

This exhaust brake assist in cruise is disabled when one of the following conditions are met:� The exhaust brake in cruise mode is not programmed.� The exhaust brake request switch is OFF.� Cruise control mode is disabled.� The accelerator pedal is pressed.� The actual vehicle speed is less than the Cruise set speed.

The cruise control system can be programmed for relaxed cruise control. This option allows the ECMto control the vehicle speed within ±8 km/h (5 mph) of the cruise set speed for smoother operation.The ECM default for this option is Off.


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Exhaust Brake System

Exhaust Brake Options Programming

The Exhaust Brake Option Programming must be done when any of the following procedures are performed:

� When the ECM is replaced.� When a change of the exhaust brake setting is needed.� When a change of the exhaust brake assist in cruise control is needed. Refer to Cruise

Control System.

The ECM has the functionality to accommodate one of three different exhaust brake systems. Thesesystems consist of the following:

� Manual Mode� Coast Mode� Latch Mode

Manual Mode

This exhaust brake control is active when the following conditions are met:� The exhaust brake switch is ON.� The accelerator pedal is fully released.

Coast Mode

This exhaust brake control is active when the following conditions are met:� The exhaust brake switch is ON.� The accelerator pedal is fully released.� The brake pedal is depressed.

Latch Mode

This exhaust brake control is active when the following conditions are met:� The exhaust brake switch is ON.� The accelerator pedal is fully released.� The brake pedal is operating and exhaust brake control continues after releasing. When the

engine speed reaches a set point speed, the exhaust brake becomes inactive.


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Vehicle Speed Limit System

Vehicle Speed Limit Options Programming

The Vehicle Speed Limit Option Programming must be done when any of the following procedures are performed:

� The ECM is replaced.� The top vehicle speed limit is changed.

The maximum vehicle speed can be changed within the following allowable range:� Minimum � 0 km/h (0 mph)� Maximum � 118 km/h (74 mph)

Gear Down Protection System

Gear Down Protection Options Programming

The Gear Down Protection Option Programming must be done when any of the following proceduresare performed:

� When the ECM is replaced.� When a change of the Gear Down Protection setting is needed.

Gear Down Protection Active Vehicle Speed

The Gear Down Protection active vehicle speed can change by request of a user within the followingallowable range:

� Minimum � 48 km/h (30 mph)� Maximum � 120 km/h (75 mph)� Preset Value � 75 km/h (45 mph)

Gear Down Protection RPM Limit

The Gear Down Protection RPM limit can change within the following allowable range:� Minimum � 1700 RPM� Maximum � 2550 RPM� Preset Value � 1700 RPM


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Engine Idle Speed Programming

Engine Idle Speed Programming

The Idle Engine Speed Option Programming must be done when any of the following procedures are performed:

� When the ECM is replaced.� When change of the Idle Engine Speed setting is needed.

Normal Idle Engine Speed Set

The Base Idle Speed can change within the following allowable range:� Minimum � 600 RPM� Maximum � 700 RPM� Preset Value � 600 RPM

High Idle Cold Engine Speed Set

The ECM has the capability to add a preset RPM on top of the normal idle engine speed at anytemperature below 0°C (32°F) to aid in engine warm-up. This function is already programmed into the ECM and cannot be disabled. However, the added engine speed can be set within the following ranges:

� Minimum � 0 RPM� Maximum for automatic transmission � 100 RPM� Maximum for manual transmission � 200 RPM� Preset Value � 0 RPM

Vehicle Speed Sensing System

Refer to Speed Calibration Programming.


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Speed Axle Calibration

The 2 Speed Axle Calibration Option Programming must be done when any of the followingprocedures are performed:

� When the ECM is replaced.� When a change of the 2 Speed Axle Calibration is needed.

The 2 Speed Axle Ratio can change within the following allowable range:� Low Axle Speed adjust set:

� Minimum � 0� Maximum � 16� Preset value � 1

� High Axle Speed adjust set:� Minimum � 0� Maximum � 16� Preset value � 1


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ui bulletin # 74 - gm upfitter · 2020. 6. 13. · f2 auto/f2 manual/f3 normal engine idle will...

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