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FAULT CODE 432 (ISS)

Accelerator Pedal Circuit

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Overview

ISS

CODE REASON EFFECT
Fault Code: 432
PID: P091
SPN: 91
FMI: 11
LAMP: Red
SRT: 00-612

Voltage detected at idle validation on-idle signal pin 6 of the OEM harness connector when voltage at accelerator position signal pin 11 of OEM harness connector indicates pedal is
not at idle or voltage detected at idle validation off-idle signal pin 9 of the OEM harness connector when voltage at accelerator position signal pin 11 of the OEM harness connector indicates pedal is at rest.

Engine will
only idle.

Accelerator Pedal Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The accelerator pedal assembly relays the accelerator percentage needed to the electronic control module (ECM).

Component Location

The accelerator position sensor is located on the accelerator pedal.

Shop Talk

Confirm that the idle validation switch is properly calibrated. Refer to the manufacturer’s instructions for adjustment information.

  • Make sure there are no external circuits hooked into the accelerator position sensor circuit and that there are no signs of tampering in the circuit.
  • If all of the wiring and the sensor checks out, replace the accelerator position sensor 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 truck with the test wires in place. If the fault goes away, replace the OEM harness. Seal openings in the bulkhead around the connector and the wires to prevent toxic and noxious fumes from entering the operator area. Check that the three accelerator position sensor circuit wires are twisted together.
  • The ECM and accelerator pedal assembly
    must be electrically calibrated to each other for proper engine response. The ECM and accelerator pedal assembly
    must be calibrated when an accelerator pedal is initially installed, replaced, when an ECM is replaced, when a new calibration is downloaded to the ECM, and when the accelerator pedal wiring is disconnected while the vehicle keyswitch is in the ON position.
  • With the keyswitch ON, gradually push the accelerator to the floor and release. Depress and release the accelerator pedal three times. This procedure will recalibrate the ECM and accelerator pedal.
  • Confirm with the OEM that the throttle is within OEM specifications for accelerator position sensor voltage or resistance at idle to off-idle transition.
  • Depressing the throttle while starting the engine is
    not necessary nor advised. Additional fueling is
    not possible until the engine reaches idle, and in older versions of software, depressing the throttle could cause Fault Code 432 in some situations.

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 following test leads when taking a measurement:
Part Number 3823995 – male Weather Pack™ test lead
Part Number 3823996 – female Weather Pack™ test lead
Part Number 3822758 – male Deutsch™/AMP®/Metri-Pack™ test lead
Part Number 3822917 – female Deutsch™/AMP®/Metri-Pack™™ test lead
Part Number 3823255 – 3-pin Metri-Pack™ repair connector
Part Number 3824910 – 6-pin Metri-Pack™ repair connector.

Troubleshooting Steps

STEPS SPECIFICATIONS
STEP 1. Check the accelerator pedal.  
  STEP 1A. Inspect the accelerator connector pins. No damaged pins
  STEP 1B. Check the resistance of the accelerator position sensor. Released: 1500 to 3000 ohms, depressed: 200 to 1500 ohms
  STEP 1C. Check for an open circuit of the accelerator position sensor supply and return circuit. 2000 to 3000 ohms
  STEP 1D. Check for a short circuit to ground in the accelerator position sensor. More than 100k ohms
  STEP 1E. Check percentage of accelerator pedal. 3 to 10 percent
STEP 2. Check the OEM harness.  
  STEP 2A. Inspect the OEM harness, bulkhead connector, and ECM connector pins. No damaged pins
  STEP 2B. Check for an open circuit in the OEM harness. Less than 10 ohms
  STEP 2C. Check for a short circuit to ground. More than 100k ohms
  STEP 2D. Check for a short circuit from pin to pin. More than 100k ohms
STEP 3. Check the ECM.  
  STEP 3A. Check the voltage supply. 4.75 to 5.25-VDC
  STEP 3B. Measure the accelerator position signal voltage. Less than 1-VDC
STEP 4. Clear the fault codes.  
  STEP 4A. Disable the fault code. Fault Code 432 inactive
  STEP 4B. Clear the inactive fault codes. All fault codes cleared.

Guided Step 1 – Check the accelerator pedal.

Guided Step 1A – Inspect the accelerator connector pins.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the accelerator from the OEM harness.
  • Flush and clean the connector pins using electronic contact cleaner, Part Number 3824510.

Action

Inspect the accelerator connector pins for:

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

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

OK NOT OK

No damaged pins

Repair or replace the accelerator pedal assembly.

  • Flush the dirt, debris, or moisture from the connector pins, use electronic contact cleaner, Part Number 3824510.
  • Repair or replace the accelerator pedal assembly. Refer to the OEM troubleshooting and repair manual.

Guided Step 1B – Check the resistance of the accelerator position sensor.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness from the accelerator position sensor.

Action

Check the resistance of the accelerator position sensor.

  • Measure the resistance from the +5 VDC supply pin to the signal pin on the sensor side of the accelerator position sensor connector with the pedal in the released (idle) position.
  • Measure the resistance from the +5 VDC supply pin to the signal pin on the sensor side of the accelerator position sensor connector with the pedal in the depressed (full fuel) position.

Note: Resistance when the pedal is released
must be at least 1000 ohms greater than when it is depressed.

Note: Install a 3-pin repair connector, Part Number 3829255, into the accelerator position sensor for idle validation switch and a 6-pin repair connector, Part Number 3824910, for integrated sensor switch.
SMALL | MEDIUM | LARGE
OK NOT OK

Released: 1500 to 3000 ohms, depressed: 200 to 1500 ohms

Replace the accelerator pedal assembly. Refer to the OEM troubleshooting and repair manual.

Guided Step 1C – Check for an open circuit of the accelerator position sensor supply and return circuit.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness from the accelerator position sensor.

Action

Check for an open circuit of the accelerator position sensor supply and return.

  • Measure the resistance from the +5 VDC supply pin to the return on the sensor side of the accelerator position sensor connector. (The pedal can be either released or depressed.)

Note: Install a 3-pin repair connector, Part Number 3829255, into the accelerator position sensor for the idle validation switch and a 6-pin repair connector, Part Number 3824910, for the integrated sensor switch.
SMALL | MEDIUM | LARGE
OK NOT OK

2000 to 3000 ohms

Replace the accelerator pedal assembly. Refer to the OEM troubleshooting and repair manual.

Guided Step 1D – Check for a short circuit to ground in the accelerator position sensor.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness from the accelerator position sensor.

Action

Check for a short circuit to ground in the accelerator position sensor.

  • Measure the resistance from the +5-VDC supply pin on the sensor side of the accelerator position sensor connector to chassis ground.
  • Measure the resistance from the signal pin on the sensor side of the accelerator position sensor connector to chassis ground.

Note: Install a 3-pin repair connector, Part Number 3829255, into the accelerator position sensor for the idle validation switch and a 6-pin repair connector, Part Number 3824910, for the integrated sensor switch.
SMALL | MEDIUM | LARGE
OK NOT OK

More than 100k ohms

Replace the accelerator pedal assembly. Refer to the OEM troubleshooting and repair manual.

Guided Step 1E – Check percentage of accelerator pedal.

Conditions

  • Disconnect the accelerator position sensor at the accelerator pedal.
  • Turn keyswitch ON.

Action

Check for percentage change of accelerator position sensor, at the accelerator pedal, during switch transition from idle to off-idle to verify within specifications.
OK NOT OK

3 to 10 percent

Replace accelerator pedal assembly. Refer to the OEM troubleshooting and repair manual.

Guided Step 2 – Check the OEM harness.

 CAUTION 

To reduce the possibility of damaging a new ECM, all other active fault codes must be investigated prior to replacing the ECM.
Guided Step 2A – Inspect the OEM harness, bulkhead connector, and ECM connector pins.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness connector from the ECM.
  • Flush and clean the connectors, use electronic contact cleaner, Part Number 3824510.

Action

Inspect the OEM harness, bulkhead connector, and ECM connector pins for:

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

For general inspection techniques, refer to Procedure 019-361 (component Connector and Pin Inspection) in Section 19.

OK NOT OK

No damaged pins

Repair the damaged pins.

Guided Step 2B – Check for an open circuit in the OEM harness.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness connector from the ECM.
  • Disconnect the OEM harness from the accelerator position sensor.

Action

Check for an open circuit in the OEM harness.

  • Measure the resistance from pin 18 of the OEM harness connector to pin C on the harness side of the accelerator position sensor connector.
  • Measure the resistance from pin 11 of the OEM harness connector to pin B on the harness side of the accelerator position sensor connector.
  • Measure the resistance from pin 19 of the OEM harness connector to pin A on the harness side of the accelerator position sensor connector.

Note: The accelerator position sensor uses either a 3-pin or 6-pin connector. Use the same pin numbers and letters to troubleshoot either of the connectors.
SMALL | MEDIUM | LARGE
OK NOT OK

Less than 10 ohms

Replace the OEM harness. Refer to the OEM troubleshooting and repair manual.

Guided Step 2C – Check for a short circuit to ground.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness to the accelerator position sensor.
  • Disconnect the OEM harness connector from ECM.

Action

Check for a short circuit to ground.

  • Measure the resistance from pin 18 in the OEM harness connector to engine block ground.
  • Measure the resistance from pin 11 in the OEM harness connector to engine block ground.
SMALL | MEDIUM | LARGE
OK NOT OK

More than 100k ohms

Replace the OEM harness. Refer to the OEM troubleshooting and repair manual.

Guided Step 2D – Check for a short circuit from pin to pin.

Conditions

  • Turn keyswitch OFF.
  • Disconnect the OEM harness from the accelerator position sensor.
  • Disconnect the OEM harness connector from the ECM.

Action

Check for a short circuit from pin to pin.

  • Measure the resistance from pin 18 in the OEM harness to all other pins in the connector.
  • Measure the resistance from pin 11 in the OEM harness to all other pins in the connector.
  • Measure the resistance from pin 19 in the OEM harness to all other pins in the connector.
  • Set all switches in cab to OFF or NEUTRAL position – open service brake switch, AC pressure switch, and clutch switch, or unplug them.
  • Diagnostic switch
    not in diagnostic mode.
SMALL | MEDIUM | LARGE
OK NOT OK

More than 100k ohms

Replace the OEM harness. Refer to the OEM troubleshooting and repair manual.

Guided Step 3 – Check the ECM.

Guided Step 3A – Check the voltage supply.

Conditions

  • Disconnect the OEM harness connector from the ECM.
  • Turn keyswitch ON.

Action

Check the voltage supply at the ECM.

  • Measure the voltage from pin 18 to pin 19 of the ECM’s OEM port.
SMALL | MEDIUM | LARGE
OK NOT OK

4.75 to 5.25 VDC

Guided Step 3B – Measure the accelerator position signal voltage.

Conditions

  • Disconnect the OEM harness connector from the ECM.
  • Turn keyswitch ON.

Action

Measure the accelerator position signal voltage.

  • Measure the voltage from pin 11 to pin 19 of the ECM’s OEM port.
SMALL | MEDIUM | LARGE
OK NOT OK

Less than 1 VDC

Guided Step 4 – Clear the fault codes.

Guided Step 4A – Disable the fault code.

Conditions

  • Turn keyswitch ON.
  • Connect all the components.

Action

Disable the fault code.

  • Depress the accelerator pedal to the full-fuel position.
  • Release the accelerator pedal.
  • Repeat this procedure twice.
  • Use INSITE™ electronic service tool to read the active fault codes.
SMALL | MEDIUM | LARGE
OK NOT OK

Fault Code 432 inactive

Fault Code 432 active.

Guided Step 4B – Clear the inactive fault codes.

Conditions

  • Connect all the components.

Action

Clear the inactive fault codes.

  • Use INSITE™ electronic service tool to clear the inactive fault codes.
OK NOT OK

All fault codes cleared

Troubleshoot any remaining active fault codes.
Repair complete
Appropriate troubleshooting chart
Last Modified:  18-Oct-2007
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