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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
C0420high severityChassis

Pre-Collision System Malfunction

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

What this code means

General fault in the pre-collision system that prepares or initiates emergency braking.

Symptoms

  • Pre-collision system warning light
  • Automatic emergency braking disabled
  • Forward collision alert unavailable
  • Driver assist systems degraded

Common causes

  • Radar or camera sensor fault
  • Control module failure
  • Brake system fault preventing intervention
  • CAN communication error between modules

Diagnostic steps

  1. Check for radar and camera codes first
  2. Verify brake system is fully operational
  3. Test CAN communication between PCS modules
  4. Check all sensor alignments
  5. Inspect wiring to PCS components

Repair notes

Diagnose root sensor or communication fault. PCS depends on multiple subsystems.

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