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CM870 and ISX Engines – FAULT CODE 387

Accelerator Pedal Position Sensor Supply Voltage Circuit


Overview

CODE REASON EFFECT
Fault Code: 387
PID: S221
SPN: 1043
FMI: 3/3
LAMP: Amber
SRT: 

Accelerator Pedal Position Sensor Supply Voltage Circuit – shorted high. High voltage detected at sensor supply circuit for the accelerator pedal position sensor.

Engine will only idle.
Accelerator Pedal Position Sensor Supply Voltage Circuit
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Circuit Description

The ECM supplies the accelerator pedal position sensor with +5 VDC.

Component Location

The accelerator pedal assembly is located in the cab.

Shop Talk

This fault is logged when the ECM senses more than 5.25 volts on the accelerator pedal position +5 volt supply line. This can be caused by a short circuit to a voltage source in the OEM harness or a short circuit to an actuator signal circuit that is greater than +5 VDC.

Refer to Troubleshooting Fault Code t05-387

Last Modified:  01-Sep-2010
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