P2500 – Generator Lamp/L Terminal Circuit Low

Description

The ECM detects a low signal at the generator L terminal.

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Symptoms

  • Battery warning light
  • Dim headlights
  • Hard starting

Causes

  • Faulty alternator
  • Wiring short to ground
  • Poor electrical connections

Diagnosis

  • Measure alternator output
  • Inspect L-terminal wiring
  • Check battery condition

Repair

  • Replace alternator
  • Repair wiring
  • Clean connections