Idle Air Control Valve Position Sensor

FAULT ID
55

TITLE
Idle Air Control (IAC) Valve Position Sensor

BACKGROUND
- If there is a malfunction of the IAC system, IAC valve position does not change even when the IAC motor was driven.
- The engine control module checks the IAC valve position sensor signal when the IAC motor was driven.

RANGE OF CHECK
- Battery voltage is 10 V or more.
- When the valve position is between steps 6 - 90, opening operation at steps below 5 and closing operation at steps above 91.

SET CONDITIONS
The sensor output voltage does not change (no pulse signal input) even when the idle air control motor operates for approx. 0.5 seconds.

EFFECT
Limp-in
- The idle revolution is not controlled.

PROBABLE CAUSES
- IAC valve position sensor failed.
- Open or shorted IAC valve position sensor circuit, or loose connector.
- IAC motor failed.
- Open or shorted IAC motor circuit, or loose connector.
- Engine control module failed.