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OBD Codes > Subaru > p0505

Subaru Information

DATSC provides free error code information for Subaru vehicles and is provided free of charge.


Idle Air Control System


Symptoms may include: MIL (Malfunction Indicator Lamp) illumination Engine stalls and may not idle unless throttle is depressed Intermittently stalls when letting off the throttle Engine may idle too high


Potential causes of an P0505 code include: IAC motor connector is damaged (check connector and pins for damage, and moisture) One or more IAC circuits open or shorted to ground One or more IAC circuits are shorted to voltage IAC has failed PCM ha


This should be a fairly straightforward diagnosis. Start by clearing the fault codes. Then unplug the IAC and start the engine (This may cause other IAC codes to set. Just ignore them for now). If the P0505 code doesn't reset, replace the IAC. It is inter


The IAC (Idle Air Control) valve controls the idle speed of the engine. At idle the throttle plate is closed, of course. The IAC is computer controlled and allows only a certain amount of air around the throttle plate. This metered air controls the idle s

Idle Control System Malfunction