P0505: Idle Air Control System Malfunction (All Others)

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2004 Mercury Sable, 2004 Mercury Mountaineer, 2004 Mercury Monterey, 2004 Mercury Marauder, and 2004 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

P0505 - IDLE AIR CONTROL SYSTEM MALFUNCTION (ALL OTHERS)

Description:	The PCM attempts to control engine speed during the KOER self-test. The test fails when the desired RPM could not be reached or controlled during the self-test.
Possible Causes:	IAC circuit open. VPWR to IAC solenoid open. IAC circuit shorted to PWR. Air inlet is plugged. Damaged IAC valve. Damaged PCM.
Diagnostic Aids:	The IAC solenoid resistance is 6 to 13 ohms. Monitor the IAC PID duty cycle and/or voltage.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
All others	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.	GO to PINPOINT TEST KE: IDLE AIR CONTROL (IAC) VALVE Step 2.