P2502
PowertrainCharging Systemhigh severityCharging System Voltage
What P2502 Means
The system charging voltage is outside the expected regulation window.
Symptoms
- Battery light
- Check engine light
- Electrical accessories malfunction
- Battery drains overnight
Common Causes
- Failed alternator
- Loose drive belt
- Battery terminal corrosion
- ECM-controlled charging fault
Diagnostic Steps
- Check battery voltage engine off and running
- Inspect belt tension and condition
- Load test alternator
- Check battery terminals
Where to start: Replace alternator or battery. Clean terminals. Check belt.
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