Common Symptoms
- Intermittent stalling or rough idle
- Check Engine Light illuminated
- Electrical accessories behaving erratically
- Dimming headlights or flickering interior lights
- Hard starting or no-start condition
- Transmission shifting irregularly
Most Likely Root Causes
- Failing alternator or voltage regulator
- Weak or failing battery
- Loose or corroded battery terminals or ground connections
- Damaged alternator wiring harness
- Faulty PCM power supply circuit
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Component Location
The alternator is typically mounted on the engine accessory drive system, with the battery located in the engine bay or trunk area.
Manufacturer Notes
Some vehicles may experience this code due to aftermarket accessory loads exceeding charging system capacity or poor-quality replacement alternators.
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