Accelerator Pedal or Lever Idle Validation Circuit – Data Erratic, Intermittent, or Incorrect
|Fault Code: 431
Accelerator Pedal or Lever Idle Validation Circuit – Data Erratic, Intermittent, or Incorrect. Voltage detected simultaneously on both idle validation and off-idle validation switches.
Automotive: Engine will only idle.
Marine: Severe derate in engine speed. Limp home capability only.
Accelerator Pedal or Lever Idle Validation Circuit
The idle validation switch is used by the electronic control module (ECM) to indicate when the accelerator pedal or lever 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 or lever position.
The nonintegrated sensor switch (NISS) is located on the accelerator pedal or lever assembly.
- 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 or lever 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 or lever assembly, it must be calibrated before operating the engine. To calibrate, turn the keyswitch to ON position and fully depress and release the pedal or lever three times.