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2021 LINCOLN NAVIGATOR
3.5L EcoBoost V6•RWD•AUTOMATIC•gas•turbo
12 active safety recalls on this vehicle — view recalls
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Repairs0Labor478Torque1914Fluid8DTC1913Battery1Maintenance0Recalls12
P0621low severityPowertrain

Generator Lamp "L" Control Circuit

on 2021 Lincoln Navigator 3.5L EcoBoost V6 · RWD

What this code means

The PCM detected a fault in the generator lamp (L terminal) control circuit. The charge warning indicator may not operate correctly.

Symptoms

  • Charge light stays on or off
  • Charging issues
  • Warning lamp malfunction

Common causes

  • Faulty generator L terminal circuit
  • Wiring open or short
  • Corroded connector
  • Faulty alternator

Diagnostic steps

  1. Check L terminal circuit continuity
  2. Inspect connectors for corrosion
  3. Test alternator output
  4. Repair circuit or replace alternator
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