U0146high severityNetwork
Lost Communication with Gateway Module A
on 2021 Mazda Mazda3 2.5L I4 · FWD
What this code means
Cannot communicate with the central gateway module that routes data between vehicle networks.
Symptoms
- Multiple systems affected
- Scan tool partial communication
- Cross-network features not working
- Intermittent multi-system faults
Common causes
- Gateway module failure
- CAN bus wiring issue
- Module power loss
- Fuse blown
- Software corruption
Diagnostic steps
- Check gateway module fuse
- Test power and ground
- Check CAN wiring on all bus connections
- Try gateway module reprogramming
- Test individual bus segments
Repair notes
Gateway module connects multiple CAN buses. Failure affects cross-bus communication. Common on German vehicles.
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