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Electronic Control System Signature, ISX and QSX15 Engines – FAULT CODE 431

Idle Validation Switch Circuit


Overview

CODE REASON EFFECT
Fault Code: 431
PID: P091
SPN: 91
FMI: 2/2
LAMP: Yellow
SRT: 

No voltage detected simultaneously on both the idle validation off-idle and on-idle signal pins.

None on performance.
Idle Validation Switch 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 solid-state switch (SSS) is located on the accelerator pedal assembly.

Shop Talk

This fault code is usually caused by a loose connection, uncalibrated accelerator pedal, or miswired idle validation switch.

Refer to Troubleshooting Fault Code t05-431sss.

Last Modified:  26-Oct-2010
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