Code result
P0508
Idle Air Control System Circuit Low
Moderate severity
What it means
The control line to the idle air control valve - which opens a small bypass around the throttle to set idle airflow - is shorted to ground or measures a voltage below the plausible level.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Control line shorted to ground
highOne of the most commonly reported causes for this code — check this first.
IAC solenoid internally shorted
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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