U0201moderate severityNetwork
Lost Communication with Headlamp Control Module
on 2001 Mazda MX-5 Miata 1.8L I4 · RWD
What this code means
Cannot communicate with the headlamp control or adaptive headlamp module.
Symptoms
- Headlights not activating
- Auto headlights disabled
- Adaptive headlights not swiveling
- DRL malfunction
Common causes
- Headlamp module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Headlamp assembly failure
Diagnostic steps
- Check headlamp module fuse
- Test power and ground
- Check CAN wiring
- Test headlamp assembly
- Inspect wiring at headlamp connector
Repair notes
Check fuses and headlamp connector. Adaptive headlamp motors inside lamp assembly can fail.
Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus