U0140high severityNetwork
Lost Communication with Body Control Module
on 2003 Mazda B2300 2.3L I4 · FWD
What this code means
Cannot communicate with the BCM.
Symptoms
- Multiple electrical features inoperative
- Lighting issues
- Lock/unlock not working
- Warning lights on
Common causes
- BCM power failure
- CAN bus issue
- BCM failure
- Water damage
Diagnostic steps
- Check BCM fuses
- Test power and ground
- Check CAN wiring
- Inspect for water damage
Repair notes
Check for water intrusion (common BCM failure cause). Check fuses.
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