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For 1990-2009 cars only

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 than the 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 arbitrarily selecting one of multiple preset, up to four not including PTO base idle speed, engine speeds as the PTO 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 engine speed 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.

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.

Important: 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 mode to set the PTO Set speed, one fixed engine speed, when this switch is pressed. The switch is a momentary 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 PTO mode to set the PTO Resume Speed, another fixed engine speed, when this switch is operated. The switch 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.

Important: 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 Set switch, the same engine speed as the PTO Set Speed, when this switch is pressed. The function of this switch is the same as the Cruise Set/Coast switch in the cab. The switch needs to be a momentary switch. The upfitter PTO connector is 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 Set switch engine speed uses the PTO Resume Speed value.

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

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

Remote Set Speed B Switch

Important: The Remote Set Speed A/B switches engine speed can change within the following allowable 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 PTO connector equipped with an input circuit to the ECM 90 of C-1 connector through C of C209 connector.

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 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 a PTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay is controlled via the ECM grounding the relay coil control circuit. The input circuit is connected to the ECM 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, usually located 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 relay turned ON, the ECM should detect a high voltage at the PTO Feedback switch input. This momentarily high input will allow the operator to use any of the PTO speeds above the PTO base idle speed until the PTO 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.

PTO Engine Shutdown Switch

Important: 

   • The time preceding the engine shutdown once the input has been received can be set within the following allowable range for: PTO Engine Shutdown Time Delay:
      - Minimum - 0 seconds
      - Maximum - 255 seconds
      - Preset value - 0 seconds
   • The PTO Engine Shutdown must be enabled, programmed, in the ECM, AND the ECM must detect a low voltage input at pin 94 of C-1 connector. These are both necessary for this shutdown 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 circuit to the ECM 94 of C-1 connector through the B of C104 connector.

Stationary Variable PTO Mode

Important: In Stationary Variable PTO mode, the PTO control is performed while the vehicle is stopped 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 engine speed 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.

Cruise Set/Coast Switch

Important: The PTO Decreased RPM Rate, decrement by a pressing, can change within the following allowable 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 mode to decrease the engine speed when this switch is tapped or while this switch is pressed. The switch is a momentary switch. The input circuit is connected to the ECM 48 of C-1 connector.

Cruise Resume/Accel. Switch

Important: The PTO Resume/Accel. Switch Increase RPM rate, increment by a tapping, uses the PTO Increase RPM Rate value. The PTO Increase RPM Rate, increment by a pressing, can change within the following allowable 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 PTO mode to increase the engine speed when this switch is tapped or while this switch is operating. The switch 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 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 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 upfitter PTO 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 PTO Increase 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 is same 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.

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 the ECM 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, DTC P2005 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 or decrease 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-1 connector through the 1 of C120 connector. The ECM also provides a ground on the low reference circuit from the ECM 10 of C-1 connector through the 3 of C120 connector. The ECM monitors the sensor 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 except the 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 a PTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay is controlled via the ECM grounding the relay coil control circuit. The input circuit is connected to the ECM 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 usually located 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 relay turned ON, the ECM should detect a high voltage at the PTO Feedback Switch input. This momentarily high input will allow the operator to use any of the PTO speeds above the PTO Base Idle Speed until PTO 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.

PTO Engine Shutdown Switch

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 must detect a low voltage input at pin 94 of C-1 connector. These both are necessary for this shutdown 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 circuit to the ECM 94 of C-1 connector through the B of C104 connector.

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 the following 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 PTO mode, 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 arbitrarily selecting engine speeds as the PTO desired engine speed. The system allows increases or decreases the PTO base idle speed by two switch inputs into the ECM while the vehicle is running.

Hardware Configuration

Mobile Variable mode uses only switches in the cab, and 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
   • 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 engine speed 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.

Cruise Set/Coast Switch

Important: The PTO Decrease RPM Ramp Rate, decrement by a pressing, can change within the following allowable 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 mode to decrease the engine speed when this switch is tapped or while this switch is pressing. The switch is a momentary switch. The input circuit is connected to the ECM 48 of C-1 connector.

Cruise Resume/Accel. Switch

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 following allowable 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 PTO mode to increase the engine speed when this switch is tapped or while this switch is pressed. The switch 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 except the PTO base idle speed.

The upfitter-installed PTO Engage Relay can be used to supply switched battery voltage to operate a PTO hydraulic solenoid. The solenoid in turn allows fluid to flow to a PTO hydraulic pump. The relay is controlled via the ECM grounding the relay coil control circuit. The input circuit is connected to the ECM 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, usually located 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 relay turned ON, the ECM should detect a high voltage at the PTO Feedback switch input. This momentarily high input will allow the operator to use any of the PTO speeds above the PTO base idle speed until the PTO mode is cancelled. The upfitter PTO connector is equipped with a voltage feed circuit to the PTO 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.

PTO Engine Shutdown Switch

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 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 must detect a low voltage input at pin 94 of C-1 connector. These both are necessary for this shutdown 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 circuit to the ECM 94 of C-1 connector through the B of C104 connector.

Fast Idle Mode

In Fast Idle mode, the engine idle speed control is performed while the vehicle is stopped by turning on the high idle switch. There is only one preset engine speed for the function. Also, the ECM will only allow 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

Hardware Configuration

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:
      - Minimum - 600 RPM
      - Maximum - 2550 RPM
      - Preset value - 1000 RPM
   • 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 enable the Fast Idle Set Speed, one fixed engine speed, when this switch is pressed. The switch is a momentary switch. The input circuit is connected to the ECM 68 of C-1 connector.

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 following allowable 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 vehicle speed. 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 ECM to 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.

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. These systems 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.

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 procedures are 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 following allowable 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

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 any temperature 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 .

Speed Axle Calibration

The 2 Speed Axle Calibration Option Programming must be done when any of the following procedures 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