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2021 MAZDA MX-5 MIATA

2.0L I4RWDMANUALgas
Repairs0Labor512Torque2472Fluid7DTC919Battery0Maintenance0Recalls0
C0501moderate severityChassis

Transfer Case Control Module Communication

on 2021 Mazda MX-5 Miata 2.0L I4 · RWD

What this code means

Loss of communication between the transfer case module and other vehicle systems.

Symptoms

  • 4WD light flashing
  • Service 4WD warning
  • Cannot select drive modes
  • Transmission may default to limp mode

Common causes

  • CAN bus wiring fault to module
  • Module connector disconnected
  • Module power loss
  • CAN bus termination issue

Diagnostic steps

  1. Check CAN wiring to transfer case module
  2. Inspect module connector
  3. Verify power and ground at module
  4. Look for U-codes related to transfer case
  5. Check CAN bus resistance

Repair notes

Repair CAN wiring or connector. Replace module if communication chip failed.

Other Chassis codes on this vehicle

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