Idle Air Control Motor Circuits
IDLE AIR CONTROL MOTOR CIRCUITSWhen Monitored
With the ignition on, battery voltage greater than 10.0 volts, and the idle air control motor active.
Set Condition
The Powertrain Control Module (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 help 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.
- Driver circuits shorted together.
- Failed PCM.
- Shorted IAC motor.
- Connector terminals.
- Connector wires.
NOTE: The PCM cannot detect an open driver circuit or a stuck motor.