ISB/ISBe Series Engines – FAULT CODE 432

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Overview

Accelerator Pedal Circuit SMALL | MEDIUM | LARGE

Circuit Description

The accelerator pedal assembly relays the accelerator percentage requested by the operator to the electronic control module (ECM). Percent accelerator is used to determine fueling. The accelerator position sensor and the idle validation switch on the accelerator pedal are adjusted at the factory to provide the correct output signals.

Note: The connector pin letters shown for the accelerator pedal wiring in these troubleshooting steps are examples of representative sensors. The connector pin assignments can vary with equipment manufacturer, but the base troubleshooting logic will still apply.

Component Location

The accelerator position sensor is located on the accelerator pedal.

Shop Talk

Confirm that the idle validation switch is properly calibrated. Use the manufacturer’s procedures 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 (stripped wires, cut loom, or additional connectors in the accelerator circuit) in the circuit.
• If all the wiring and the sensor checks look good, replace the accelerator position sensor and the idle validation switch circuit wires, between the accelerator pedal and ECM, with new wires. Run the twisted pair of 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 seeping into the operator area. Note: Check that the three accelerator position sensor circuit wires are twisted together. Check that the three idle validation switch 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 ON.
• With 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 OEM that the accelerator is within OEM specifications for accelerator pedal sensor voltage or resistance at idle to off-idle transition.
• Depressing the accelerator 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 accelerator could cause Fault Code 432, in some situations.

Refer to Troubleshooting Fault Code t05-432