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2021 MAZDA MAZDA3

2.5L I4FWDAUTOMATICgas
1 active safety recall on this vehicle — view recalls
Repairs0Labor479Torque3805Fluid6DTC919Battery0Maintenance0Recalls1
C0121high severityChassis

Electronic Parking Brake Motor Overcurrent

on 2021 Mazda Mazda3 2.5L I4 · FWD

What this code means

The EPB motor is drawing more current than the module can supply.

Symptoms

  • EPB warning light
  • Parking brake partially applied
  • Grinding noise when EPB activates
  • EPB applies slowly

Common causes

  • EPB motor seized or binding
  • Brake caliper seized
  • EPB cable or mechanism corroded
  • Motor brushes worn

Diagnostic steps

  1. Command EPB apply and release, monitor current draw
  2. Inspect rear brake calipers for binding
  3. Check EPB mechanism for corrosion
  4. Test motor current draw with ammeter
  5. Lubricate EPB mechanism if accessible

Repair notes

Replace EPB motor or caliper if mechanism is seized. Clean and lubricate if corrosion is the cause.

Other Chassis codes on this vehicle

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