Idle Air Control Motor Circuits

Name of Code:
Idle Air Control (IAC) Motor Circuits

When Monitored:
At key on and battery voltage greater than 11.5 volts.

Set Condition:
The PCM senses a short to ground or battery voltage on any of the four IAC driver circuits for 2.75 seconds while the IAC motor is active.

Theory of Operation:
The idle air control motor is used by the PCM to regulate idle speed. The motor controls the amount of air allowed to bypass the throttle blade. The PCM controls the motor using four driver circuits to position the stepper motor.

Possible Causes:
- Driver circuit shorted to ground
- Driver circuit shorted to battery voltage
- Driver circuits shorted together
- Failed PCM
- Shorted AC motor
- Connector terminals
- Connector wires