What does code P0511 mean?

Q: What does code P0511 mean?

Idle Air Control Circuit. P0511 indicates that the powertrain control module (PCM) has detected an electrical fault in the idle air control (IAC) circuit, which manages engine idle speed by bypassing air around the throttle plate. The PCM monitors the IAC valve's electrical circuit and sets this code when the commanded current or voltage does not match expected values, or when the circuit is open, shorted, or out of range.

DTC codes / P05xx · Vehicle speed, idle control and auxiliary inputs / P0511

P0511Idle Air Control Circuit

P0511 indicates that the powertrain control module (PCM) has detected an electrical fault in the idle air control (IAC) circuit, which manages engine idle speed by bypassing air around the throttle plate. The PCM monitors the IAC valve's electrical circuit and sets this code when the commanded current or voltage does not match expected values, or when the circuit is open, shorted, or out of range.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaVehicle speed, idle control and auxiliary inputs

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.