Lost Communication with Mirror Control Module
2002-2002 Mazda B2300 2.3L I4
The 2002 Mazda B2300 is equipped with a 2.3L inline-4 engine. Below you'll find detailed u0204 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
Cannot communicate with the power mirror or auto-dimming mirror control module.
Symptoms
- Mirror adjustment not working
- Auto-dimming not functioning
- Mirror memory not working
- Auto-fold mirrors disabled
Common Causes
- Mirror module failure
- Wiring issue
- Module power loss
- Fuse blown
- Mirror motor failure
Diagnostic Steps
- Check mirror module fuse
- Test power and ground
- Inspect door jamb wiring
- Test mirror motors
- Check mirror switch
Repair Notes
Check door jamb wiring. Mirror wiring passes through flex point and commonly breaks.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0006High Speed CAN Communication Bus (-) Open
- U0007High Speed CAN Communication Bus (-) Low
- U0008High Speed CAN Communication Bus (-) High
- U0009High Speed CAN Communication Bus Shorted Together
- U0010Medium Speed CAN Communication Bus
U0204 on Other Vehicles
Common Questions
What does code U0204 mean on a 2002-2002 Mazda B2300?
U0204 stands for "Lost Communication with Mirror Control Module". Cannot communicate with the power mirror or auto-dimming mirror control module.
What are the symptoms of U0204 on a Mazda B2300?
Common symptoms of U0204 include: Mirror adjustment not working, Auto-dimming not functioning, Mirror memory not working, Auto-fold mirrors disabled.
What causes U0204 on a 2002-2002 Mazda B2300?
Common causes of U0204 include: Mirror module failure, Wiring issue, Module power loss, Fuse blown, Mirror motor failure.
Last updated: March 2026