P2504
PowertrainCharging Systemcritical severityCharging System Voltage High
What P2504 Means
Charging system output voltage exceeds maximum safe threshold.
Symptoms
- Battery boiling/swelling
- Bulbs burning out frequently
- Check engine light
- Electrical component damage
Common Causes
- Failed voltage regulator
- ECM charging control fault
- Ground strap issue
Diagnostic Steps
- Measure charging voltage at various RPM
- Check voltage regulator
- Inspect ground straps
Where to start: Replace alternator or voltage regulator. Check and repair grounds. Overcharging can damage expensive electronics.
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