Electronic Control System Gas Plus Engines – FAULT CODE 133

Remote Accelerator Pedal Position Sensor Circuit – Shorted High

Overview

Remote Accelerator Pedal Position Sensor Circuit – Shorted High

CODE REASON EFFECT
Fault Code: 133
PID: P029
SPN: 974
FMI: 3
LAMP: Red
SRT: 

Remote Accelerator Pedal Position Sensor Circuit – Shorted High. High voltage detected on the sensor signal pin at the ECM.

Engine will only idle if the remote accelerator is enabled.

Remote Accelerator Pedal Position Sensor Circuit

SMALL | MEDIUM | LARGE

Circuit Description

The electronic control module (ECM) uses the remote accelerator pedal position input to determine the remote accelerator pedal position.

Component Location

The remote accelerator pedal position sensor is located on the remote accelerator pedal.

Shop Talk

The remote accelerator pedal position sensor functions similarly to the accelerator pedal position sensor.

  • Make sure there are no external circuits hooked into the remote accelerator pedal position sensor circuit and that there are no signs of tampering in the circuit.
  • If all the wiring and sensor checks are okay, replace the remote accelerator pedal position sensor and the idle validation switch circuit wires, between the accelerator pedal and ECM, with new wires. Run the wires through or around the bulkhead without using the bulkhead connector. Test the vehicle with the test wires in place. If the fault code goes away, replace the OEM harness.
  • Verify that the remote accelerator pedal position sensor wires are twisted together.

Cautions and Warnings


 CAUTION 

To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM.

 CAUTION 

To reduce the possibility of pin and harness damage, use the appropriate test lead when taking a measurement.

 CAUTION 

To reduce the possibility of pin and harness damage, use the following test leads when taking a measurement:
Part Number 3822758 – male Deutsch/AMP/Metri-Pack test lead
Part Number 3823993 – male Deutsch test lead
Part Number 3823996 – female Weather-Pack test lead.

Troubleshooting Steps

STEPS SPECIFICATIONS
STEP 1. Check the fault codes.  
  STEP 1A. Check for sensor supply or multiple fault codes. Fault Code 227 active?
  STEP 1B. Check for an inactive fault code. Fault Code 133 inactive?
STEP 2. Check the remote accelerator pedal/lever and circuit.  
  STEP 2A. Inspect the remote accelerator pedal/lever and connector pins. Dirty or damaged pins?
  STEP 2B. Check the remote accelerator pedal/lever supply voltage and return circuit. 4.5 to 5.25 VDC?
  STEP 2C. Check the circuit response. Fault Code 134 active and Fault Code 133 inactive?
  STEP 2D. Check the fault codes and verify remote accelerator pedal/lever condition. Fault Code 133 active?
STEP 3. Check the ECM and engine harness.  
  STEP 3A. Inspect the ECM and engine harness connector pins. Dirty or damaged pins?
  STEP 3A-1. Check for an open circuit in the engine harness and OEM harness.
  STEP 3A-2. Check for a pin to pin short circuit in the engine harness and OEM harness.
  STEP 3B. Check for an inactive fault code. Fault Code 133 inactive?
STEP 4. Clear the fault codes.  
  STEP 4A. Disable the fault code. Fault Code 133 inactive?
  STEP 4B. Clear the inactive fault codes. All fault codes cleared?


Guided Step 1 – Check the fault codes.

Guided Step 1A – Check for sensor supply or multiple fault codes.

Conditions

  • Turn keyswitch ON to the RUN position
  • Connect the INSITE™ electronic service tool.

Action

  • Use INSITE™ electronic service tool to read the fault codes.

Fault Code 227 active?

YES NO
No Repair No Repair
Fault Code 227

Guided Step 1B – Check for inactive fault codes.

Conditions

  • Turn keyswitch ON to the RUN position
  • Turn the remote accelerator switch to ON
  • Connect the INSITE™ electronic service tool.

Action

  • Use INSITE™ electronic service tool to read the fault codes.

Fault Code 133 inactive?

YES NO
No Repair No Repair


Guided Step 2 – Check the remote accelerator pedal/lever and circuit.

Guided Step 2A – Inspect the remote accelerator pedal/lever and connector pins.

Conditions

  • Turn keyswitch OFF or RUN/STOP switch to the STOP position.
  • Disconnect the remote accelerator pedal/lever from the OEM harness.

Action

  • Corroded pins
  • Bent or broken pins
  • Pushed back or expanded pins
  • Wire insulation damage
  • Moisture in or on the connector
  • Missing or damaged connector seals
  • Connector shell damage
  • Dirt or debris in or on the connector pins.

For general inspection techniques, refer to Component Connector and Pin Inspection, Procedure 019-361.

Dirty or damaged pins?

YES NO

A defective connection has been detected in the sensor or harness connector.

  • Flush the dirt, debris, or moisture from the connector pins using electronic contact cleaner, Part Number 3824510.
  • Install the appropriate connector seal if it is damaged or missing.
  • Repair the OEM harness. Refer to the OEM troubleshooting and repair manual.
  • Replace the OEM harness. Refer to the OEM troubleshooting and repair manual.
No Repair

Guided Step 2B – Check the remote accelerator pedal/lever supply voltage and return circuit.

Conditions

  • Turn keyswitch OFF or RUN/STOP switch to the STOP position.
  • Disconnect the remote accelerator pedal/lever from the OEM harness.
  • Turn keyswitch ON to the RUN position.

Action

  • Measure the voltage between the accelerator pedal voltage SUPPLY pin and the RETURN pin at the remote accelerator pedal/lever connector of the OEM harness.

Refer to the circuit diagram or wiring diagram for connector pin identification.

4.5 to 5.25 VDC?

YES NO
No Repair No Repair

Guided Step 2C – Check the circuit response.

Conditions

  • Turn keyswitch OFF to the STOP position
  • Disconnect the remote accelerator pedal/lever from the OEM harness
  • Turn the remote accelerator switch to ON
  • Connect INSITE™ electronic service tool.

Action

  • Use INSITE™ electronic service tool to read the fault codes .

Fault Code 134 active and Fault Code 133 inactive?

YES NO
No Repair No Repair

Guided Step 2D – Check the fault codes and verify remote accelerator pedal/lever condition.

Conditions

  • Turn keyswitch OFF to the STOP position
  • Connect the remote accelerator pedal/lever to the OEM harness
  • Turn keyswitch ON to the RUN position
  • Turn the remote accelerator switch to ON
  • Connect INSITE™ electronic service tool.

Action

  • Start the engine and let idle for one minute.
  • Use INSITE™ electronic service tool to read the fault codes.

Fault Code 133 active?

YES NO

A defective remote accelerator pedal/lever has been detected. Contact the appropriate OEM or dealership for repair instructions.

  • Replace the remote accelerator/lever. Refer to the OEM troubleshooting and repair manual.
No Repair


Guided Step 3 – Check the ECM and engine harness.

Guided Step 3A – Inspect the ECM and engine harness connector pins.

Conditions

  • Turn keyswitch OFF to the STOP position
  • Disconnect ECM and engine harness connector 2.

Action

  • Corroded pins
  • Bent or broken pins
  • Pushed back or expanded pins
  • Wire insulation damage
  • Moisture in or on the connector
  • Missing or damaged connector seals
  • Connector shell damage
  • Dirt or debris in or on the connector pins.

For general inspection techniques, refer to Component Connector and Pin Inspection, Procedure 019-361.

Dirty or damaged pins?

YES NO

A defective connection has been detected in the ECM or harness connector 2.

  • Flush the dirt, debris, or moisture from the connector pins using electronic contact cleaner, Part Number 3824510.
  • Install the appropriate connector seal if it is damaged or missing.
  • Repair the engine harness. Refer to the 019-201.
  • Replace the engine harness. Refer to the 019-043
No Repair

Guided Step 3A-1 – Check for an open circuit in the engine harness and OEM harness.

Conditions

  • Turn keyswitch OFF to the STOP position
  • Disconnect the engine harness from the ECM connector 2
  • Disconnect the remote accelerator pedal/lever from the OEM harness.

Action

  • Measure the resistance between the engine harness ECM connector 2 RETURN pin and the OEM harness accelerator pedal/lever connector RETURN pin.

Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Resistance Measurements Using a Multimeter and Wiring Diagram, Procedure 019-360.

Less than 10 ohms?

YES NO
No Repair

An open circuit has been detected in the engine harness or the OEM harness.

Troubleshoot each harness connected is series to determine which contains the shorted signal circuit.

Repair or replace the engine harness or OEM harness.

  • Repair or replace the OEM harness. Refer to the OEM troubleshooting and repair manual.
  • Repair the engine harness. Refer to Procedure 019-204.
  • Replace the engine harness. Refer to Procedure 019-043.

Guided Step 3A-2 – Check for a pin to pin short circuit in the engine harness and OEM harness.

Conditions

  • Turn keyswitch OFF to the STOP position
  • Disconnect the engine harness from the ECM connector 1 and connector 2
  • Disconnect the remote accelerator pedal/lever from the OEM harness.

Action

  • Measure the resistance between the remote accelerator pedal/lever SIGNAL pin in the engine harness ECM connector 2 and all other pins in the connector 2.
  • Measure the resistance between the remote accelerator pedal/lever SIGNAL pin in the engine harness ECM connector 2 and all other pins in the connector 1.

Refer to the circuit diagram or wiring diagram for connector pin identification.

For general resistance measurement techniques, refer to Resistance Measurements Using a Multimeter and Wiring Diagram, Procedure 019-360.

Greater than 100k ohms?

YES NO
No Repair

A pin to pin short circuit on the signal line has been detected in the OEM harness and engine harness.

Troubleshoot each harness connected is series to determine which contains the shorted signal circuit.

Repair or replace the engine harness or OEM harness.

  • Repair or replace the OEM harness. Refer to the OEM troubleshooting and repair manual.
  • Repair the engine harness. Refer to Procedure 019-201.
  • Replace the engine harness. Refer to Procedure 019-043.

Guided Step 3B – Check for an inactive fault code.

Conditions

  • Connect all components
  • Turn keyswitch ON to the RUN position
  • Turn the remote accelerator switch to ON
  • Connect INSITE™ electronic service tool.

Action

  • Start the engine and let it idle for one minute.
  • Use INSITE™ electronic service tool to read the fault codes.

Fault Code 133 active?

YES NO
No Repair

Replace the ECM. Call for pre-authorization. Refer to Procedure 019-031.


Guided Step 4 – Clear the fault codes.

Guided Step 4A – Disable the fault code.

Conditions

  • Connect all components
  • Turn keyswitch ON to the RUN position
  • Turn the remote accelerator switch to ON
  • Connect INSITE™ electronic service tool.

Action

  • Start the engine and let it idle for one minute.
  • Use INSITE™ electronic service tool to verify that Fault Code 133 is inactive.

Fault Code 133 inactive?

YES NO
No Repair No Repair

Guided Step 4B – Clear the inactive fault codes.

Conditions

  • Connect all components
  • Turn keyswitch ON to the RUN position
  • Turn the remote accelerator switch to ON
  • Connect INSITE™ electronic service tool.

Action

  • Use INSITE™ electronic service tool to erase the inactive fault codes.

All fault codes cleared?

YES NO
No Repair No Repair
Repair complete

Appropriate troubleshooting charts

Last Modified:  06-Aug-2004