Common Symptoms
- Check Engine Light illuminated
- Erratic gauge readings or flickering dashboard lights
- Battery warning light on
- Intermittent electrical accessory malfunctions
- Hard starting or stalling when voltage spikes occur
- Module communication errors or multiple fault codes
Most Likely Root Causes
- Faulty voltage regulator in alternator
- Defective alternator overcharging battery
- Damaged wiring or poor ground connections in charging system
- Failing PCM voltage reference circuit
- Corroded battery terminals or cables
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Component Location
The alternator and voltage regulator are mounted on the engine block, typically driven by the serpentine belt with wiring connected to the battery and PCM.
Manufacturer Notes
Some vehicle models may set this code due to software calibration issues with voltage sensing thresholds in the PCM.
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