P1508moderate severityPowertrain
IAC Valve Closing Coil Circuit Short
on 2020 Hyundai Tucson 2.4L I4 · AWD
What this code means
The PCM has detected a short circuit in the IAC valve closing coil circuit. This may cause the idle to drop too low or the valve to behave erratically.
Symptoms
- Check Engine Light
- Low or erratic idle
- Engine stalling
- IAC valve buzzing
Common causes
- IAC closing coil internally shorted
- Wiring short to ground in closing coil circuit
- Damaged connector
- Water intrusion
- Chafed wiring
Diagnostic steps
- Test IAC closing coil resistance (abnormally low indicates short)
- Inspect wiring for damage or chafing
- Check connector for water or corrosion
- Disconnect IAC and measure circuit resistance to ground
- Swap IAC valve and retest
Repair notes
Replace the IAC valve if the closing coil is shorted; repair wiring if the short is in the harness.
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P0003
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P0005
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