U0111critical severityNetwork
Lost Communication with Battery Energy Control Module A
on 2012 Toyota Highlander 3.3L V6 Hybrid · AWD
What this code means
Cannot communicate with the hybrid/EV high-voltage battery management system.
Symptoms
- Hybrid battery warning
- Check hybrid system light
- Reduced EV range
- Vehicle may not start
- Battery temperature warning
Common causes
- Battery management module failure
- CAN bus wiring
- 12V supply loss to module
- High-voltage safety disconnect
- Module connector issue
Diagnostic steps
- Check battery management module 12V fuse
- Test 12V power and ground
- Verify HV safety interlock
- Check CAN wiring to module
- Scan for battery system codes
Repair notes
High-voltage system. Qualified technician required. Check 12V auxiliary supply first.
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