P2500
PowertrainCharging Systemhigh severityGenerator Lamp/L Terminal Circuit Low
What P2500 Means
Low signal on the alternator lamp/exciter circuit, preventing proper charging regulation.
Symptoms
- Battery light on
- Low charging voltage
- Check engine light
Common Causes
- Broken exciter wire
- Failed voltage regulator
- Corroded alternator connector
- Blown dash bulb
Diagnostic Steps
- Check charging system voltage
- Inspect alternator connector
- Measure exciter circuit voltage
Where to start: Repair exciter circuit wiring or replace alternator.
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