U0205
Lost Communication with Horn Control Module
1997-2003 Audi A8 4.2L V8
Moderate SeverityNetworkGeneric (SAE)
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
- 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
U0205 on Other Vehicles
Common Questions
What does code U0205 mean on a 1997-2003 Audi A8?
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 Audi A8?
Common symptoms of U0205 include: Horn not sounding, Horn intermittent, Panic alarm no horn output, Theft alarm no horn.
What causes U0205 on a 1997-2003 Audi A8?
Common causes of U0205 include: Horn relay module failure, CAN bus wiring, Module power loss, Fuse blown, Horn assembly failure.