Back to 1999 BMW 540iT E39

1999 BMW 540IT E39

4.4L V8RWDAUTOMATICgas
Repairs0Labor595Torque2626Fluid7DTC649Battery0Maintenance0Recalls0
P2501high severityPowertrain

Generator Lamp/L Terminal Circuit High

on 1999 BMW 540iT E39 4.4L V8 · RWD

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.

Other Powertrain codes on this vehicle

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