U0119
NetworkModule Communicationcritical severityLost Communication with Battery Energy Control Module B
What U0119 Means
Cannot communicate with the secondary battery energy module in multi-battery hybrid systems.
Symptoms
- Hybrid system warning
- Reduced battery capacity
- Limited EV operation
- Battery imbalance warnings
Common Causes
- Battery module B failure
- CAN bus wiring
- 12V supply issue
- Module connector fault
Diagnostic Steps
- Check module B fuse
- Test 12V power and ground
- Check CAN wiring
- Scan battery management system
- Check module B connector
Where to start: High-voltage system. Professional service required.
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