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2020 MAZDA MAZDA3

2.0L I4FWDAUTOMATICgas
2 active safety recalls on this vehicle — view recalls
Repairs0Labor473Torque3657Fluid6DTC919Battery0Maintenance0Recalls2
B0421moderate severityBody

ABS Warning Lamp Circuit

on 2020 Mazda Mazda3 2.0L I4 · FWD

What this code means

Malfunction in the ABS warning lamp circuit. The lamp may not illuminate or may stay on incorrectly.

Symptoms

  • ABS light does not come on during bulb check
  • ABS light always on
  • Cannot determine ABS system status
  • Light flickering

Common causes

  • Burnt out lamp
  • Cluster fault
  • ABS module lamp driver failure
  • Wiring issue

Diagnostic steps

  1. Check lamp during key-on bulb check
  2. Scan ABS module for codes
  3. Test lamp drive circuit
  4. Inspect wiring from ABS module to cluster

Repair notes

Replace ABS warning lamp or repair wiring circuit.

Other Body codes on this vehicle

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