U2004moderate severityNetwork
Network Configuration Not Learned
on 2017 Mazda Mazda3 2.5L I4 · FWD
What this code means
The vehicle network configuration has not been learned or stored after module replacement or reset.
Symptoms
- Systems not communicating properly
- Features missing after service
- Modules not recognizing each other
- Network topology error
Common causes
- Battery disconnect without relearn
- Module replacement without network setup
- Configuration data lost
- Programming interrupted
Diagnostic steps
- Perform network configuration learn procedure
- Run module discovery scan
- Program as-built data
- Perform SBL (System Bus Learn)
- Complete post-service initialization
Repair notes
Run network configuration or module discovery procedure. Required after replacing network modules.
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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