Error code
OBD2 P0509
OBD2P0509
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Idle Air Control System Circuit High.
Severity
moderateCan drive, but performance issues may occur and worsen over time.
Summary
P0509 indicates an issue with the Idle Air Control (IAC) system, specifically that the circuit voltage is too high. This code relates to the IAC valve or its wiring.
Common Causes
- Wiring short to positive
- Faulty IAC valve
- ECM malfunction
Fixes
- Replace faulty IAC valve or repair wiring issue.
FAQ
What does P0509 mean?
P0509 indicates a high voltage condition in the Idle Air Control (IAC) system circuit.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
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