P0505 - Idle Air Control System Malfunction

The Camshaft Position (CMP) sensor circuit is monitored by the Powertrain Control Module (PCM). The test fails when the change in engine speed does not coincide with PCM demand on the idle Air Control (IAC) valve.

Possible Causes:
^ IAC valve circuit shorted or open
^ IAC valve

Diagnostic Aids:
All accessories OFF. Key ON engine running at idle speed. Disconnect the Idle Air Control (IAC) valve connector. Engine speed should decrease.