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P0509

Overview

Code

P0509

Code Type

P

Code Class

P0

System

Idle Control

Severity Level

Medium

Emissions Related

true

Drivability Impact

Minor

Diagnostic Protocol

OBD2

Freeze Frame Useful

true

Code Definition

Diagnostic trouble code P0509 indicates an idle air control valve circuit range problem

Symptoms

Erratic idle; Check Engine Light

Overview applies to this diagnostic code.

Affected Systems

On This Page

  • Code Definition

  • Symptoms

  • Affected Systems

  • Possible Causes

  • Diagnostic Steps

  • Drive Safety Notes​

More Resources

Idle air control circuit

Possible Causes

Failed IAC valve; Faulty wiring

Diagnostic Steps

1 Inspect IAC valve 2 Test IAC resistance

Drive Safety Notes

Idling may become unstable

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