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 can vary 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:

• IAC valve counts are less than 2.
• Engine coolant temperature is greater than 104°f (40°C)
• Battery output is 10-17 volts.
• No presence of Codes: P0106-P0108, P0112, P0113, P0117, P0118, P0121-P0123, P0125, P0131-P0134, P0335, P0341, P0342, P0502, P0503, P0562, P0563, P0600, P1133, P1520.
• BARO is more than 72 kPa.
• Engine run time is more than 20 seconds.
• Idle speed is more than 60 RPM more than desired RPM for more than 5 seconds.