Circuit Description

The Idle Air Control (IAC) valve is controlled by the Powertrain Control Module (PCM). PCM uses the IAC to maintain a desired idle speed, which varies depending on input to PCM. Scan tool reads IAC valve pintle position in counts. The higher the counts, the more air that is allowed to by-pass the throttle plate.

Conditions for setting this DTC are as follows:

• No VSS, TP sensor, EVAP system, EVAP solenoid, misfire, IAT sensor, MAP sensor, fuel trim, fuel injector, EGR pintle position, ECT sensor, CKP sensor, or MAF sensor related DTCs set.
• BARO greater than 65 kPa.
• System voltage 9-16 volts.
• ECT greater than 122°F (50°C).
• Engine running for at least 125 seconds.