CM870 and ISX Engines – FAULT CODE 431 (NISS)

Accelerator Pedal Idle Validation Circuit


Overview

CODE REASON EFFECT
Fault Code: 431
PID: S230
SPN: 558
FMI: 2/2
LAMP: Amber
SRT: 

Accelerator Pedal Idle Validation Circuit – data incorrect. Voltage detected simultaneously on both idle validation and idle validation off-idle validation switches.

No effect on performance.

Accelerator Pedal Idle Validation Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The idle validation switch is used by the electronic control module (ECM) to indicate when the accelerator pedal is released (on-idle) or depressed (off-idle). The switch is adjusted at the factory to switch from on-idle to off-idle at the correct accelerator pedal position.

Component Location

The nonintegrated sensor switch (NISS) is located on the accelerator pedal assembly.

Shop Talk

  • This fault code is usually caused by an open circuit on either the idle validation on-idle or off-idle signal circuits, a loose connection, uncalibrated accelerator pedal assembly, or miswired idle validation switch.
  • The nonintegrated sensor switch has a different internal resistance specification (10 ohms) than the integrated sensor switch (ISS).
  • When installing a new accelerator pedal assembly, it must be calibrated before operating the engine. To calibrate, turn the keyswitch to ON position and fully depress and release the pedal three times.

Refer to Troubleshooting Fault Code t05-431niss

Last Modified:  01-Sep-2010