P2501 – Generator Lamp/L Terminal Circuit High

Description

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

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Symptoms

  • Battery warning light
  • Electrical fluctuations
  • Hard starting

Causes

  • Faulty regulator
  • Wiring short to power
  • ECM fault

Diagnosis

  • Test alternator regulator
  • Inspect wiring
  • Check ECM inputs

Repair

  • Replace alternator
  • Repair wiring