Hours: 07–23 daily

TuningBot DTC Database · v4.37.15

P0509 Idle Air Control System Circuit High

Generic (OBD-II) interpretation in the TuningBot DTC database.

P · PowertrainEngineOBD2

What P0509 means

P0509
Idle Air Control System Circuit High Generic · engine Data confidence 90%

The control module detected that the signal in the Idle Air Control System circuit stayed above the expected operating range.

Possible causes

  • Wiring short to positive
  • IAC valve
  • ECM

Related and nearby codes

How to read P0509

P

Powertrain: engine, transmission and driveline systems.

0

Generic SAE-standard code: same meaning on every make.

509

Specific fault index within the subsystem.

Frequently asked questions about P0509

What does P0509 mean?

Idle Air Control System Circuit High. The control module detected that the signal in the Idle Air Control System circuit stayed above the expected operating range.

Is P0509 generic or manufacturer-specific?

P0509 is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove P0509 at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

ECU tuningDyno-tested results by model and engine See the results →

← Search the full DTC database