P0508: Idle Air Control System Circuit Low
What to do
Usually driveable with an unstable idle. The repair is normally the valve or its wiring.
What this code means
The idle air control circuit is reading low — a short to ground, or a winding that has failed short. An electrical complaint rather than an airflow one, so the diagnosis is supply, ground and winding resistance rather than a search for leaks.
Likely causes
Start here
- Signal wire shorted to ground · moderate
- Open or shorted solenoid winding · easy
- Faulty idle air control valve · moderate
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Community experience
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