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2025 TESLA ROADSTER
Tri Motor AWD•AWD•AUTOMATIC•ev
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Repairs0Labor313Torque67Fluid7DTC726Battery1Maintenance0Recalls0
P2501high severityPowertrain

Generator Lamp/L Terminal Circuit High

on 2025 Tesla Roadster Tri Motor AWD · AWD

What this code means

High signal on alternator exciter circuit.

Symptoms

  • Battery light behavior abnormal
  • Overcharging possible
  • Check engine light

Common causes

  • Short to voltage in exciter wire
  • Voltage regulator fault
  • ECM communication issue

Diagnostic steps

  1. Measure exciter circuit voltage
  2. Check for shorts to power
  3. Test alternator output

Repair notes

Repair wiring or replace alternator.

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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