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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
C0500high severityChassis

Transfer Case Control Module Malfunction

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

What this code means

Internal fault in the transfer case control module that manages 4WD/AWD operation.

Symptoms

  • 4WD warning light
  • Service 4WD message
  • Cannot shift between 2WD and 4WD
  • Transfer case stuck in current mode

Common causes

  • Module internal failure
  • Module power supply fault
  • Software error
  • CAN communication loss
  • Overheated module

Diagnostic steps

  1. Check module power supply and ground
  2. Scan for CAN communication codes
  3. Check module connector for corrosion
  4. Attempt module reset
  5. Check for software updates

Repair notes

Replace transfer case control module. Reprogram and calibrate after installation.

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