U0205
Lost Communication with Horn Control Module
2016-2021 Mazda CX-3 2.0L I4 🇨🇦
Moderate SeverityNetwork
Description
Cannot communicate with the horn control module on vehicles with electronic horn management.
Symptoms
- Horn not sounding
- Horn intermittent
- Panic alarm no horn output
- Theft alarm no horn
Common Causes
- Horn relay module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Horn assembly failure
Diagnostic Steps
- Check horn fuse
- Test horn relay
- Check CAN wiring to horn module
- Test horn assembly directly
- Inspect steering wheel horn switch
Repair Notes
Check fuse and horn relay first. Test horn directly with jumper wire to confirm horn works.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0005High Speed CAN Communication Bus (+) High
U0205 on Other Vehicles
Common Questions
What does code U0205 mean on a 2016-2021 Mazda CX-3?
U0205 stands for "Lost Communication with Horn Control Module". Cannot communicate with the horn control module on vehicles with electronic horn management.
What are the symptoms of U0205 on a Mazda CX-3?
Common symptoms of U0205 include: Horn not sounding, Horn intermittent, Panic alarm no horn output, Theft alarm no horn.
What causes U0205 on a 2016-2021 Mazda CX-3?
Common causes of U0205 include: Horn relay module failure, CAN bus wiring, Module power loss, Fuse blown, Horn assembly failure.