IAC Valve Opening Coil Circuit Short

What this code means

The PCM has detected a short circuit in the IAC valve opening coil circuit. This can cause the IAC valve to remain energized or draw excessive current, affecting idle speed control.

Symptoms

• Check Engine Light
• Erratic idle speed
• High idle speed
• IAC valve overheating

Common causes

• Short to ground in IAC opening coil wiring
• IAC valve internal coil short
• Chafed wiring contacting ground
• Connector with bridged pins
• Water intrusion in connector

Diagnostic steps

1. Test IAC opening coil resistance (low reading indicates short)
2. Inspect wiring for chafing or damage
3. Check connector for bridged pins or water intrusion
4. Disconnect IAC and test circuit resistance to ground
5. Replace IAC valve and retest

Repair notes

Replace the IAC valve if shorted internally; repair wiring if the short is external.

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