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2020 MAZDA MAZDA3
2.5L Skyactiv-G I4 (186 hp)•AWD•AUTOMATIC•gas
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor987Torque6478Fluid16DTC2264Battery2Maintenance0Recalls2
B0401moderate severityBody

Speedometer Circuit Malfunction

on 2020 Mazda Mazda3 2.5L Skyactiv-G I4 (186 hp) · AWD

What this code means

The speedometer gauge is not functioning or is displaying incorrect speed readings.

Symptoms

  • Speedometer reads zero while driving
  • Speedometer reads erratically
  • Speedometer needle bouncing
  • Cruise control may not work

Common causes

  • Faulty vehicle speed sensor
  • Instrument cluster stepper motor failure
  • Cluster circuit board fault
  • Speed signal wiring issue

Diagnostic steps

  1. Check speed sensor signal with scan tool
  2. Compare GPS speed to speedometer
  3. Test cluster stepper motor
  4. Check speed sensor wiring
  5. Scan for related speed sensor codes

Repair notes

Replace speed sensor or instrument cluster stepper motor. If cluster board is faulty, replace or repair cluster.

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