DTC P0505: Idle Air Control (IAC) System Malfunction
- Remove IAC valve. Observe IAC rotary valve as ignition is turned on, then off. If rotary valve operates correctly, check for an intermittent problem. See TESTS W/O CODES article. If rotary valve does not operate, go to next step.
- Check continuity of Red/Yellow wire between terminal No. 2 on PCM 22-pin harness connector and IAC valve. Repair as needed. If continuity exists, replace IAC valve. Retest system.