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2021 MAZDA MAZDA3

2.5L Turbo I4FWDAUTOMATICgasturbo
1 active safety recall on this vehicle — view recalls
Repairs0Labor595Torque4705Fluid6DTC919Battery0Maintenance0Recalls1
P2501high severityPowertrain

Generator Lamp/L Terminal Circuit High

on 2021 Mazda Mazda3 2.5L Turbo I4 · FWD

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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