U0111Lost Communication With Battery Energy Control Module A
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- U0111 indicates that battery energy control module A, which measures cell voltages, temperatures and current of the high-voltage or 48 V battery, has dropped off the network. GM's 2018 Volt hybrid controller expects it on bus A and sets the code as Type B over two trips once messages have been absent for 5 s above 10.2 V; while it is pending, GM suspends pack voltage and current plausibility checks. GM PIC5829 (Volt 2011–2013) advises updating the BECM calibration instead of replacing it. In the Jeep Wrangler 4xe the battery module may fail to wake in severe cold, so the hybrid controller logs U0111-00 (case S2108000056). Land Rover reports 48 V MHEV BECMs going offline with MIL and lost start-stop. U0112 is module B.
- What you may notice
- MIL or service-hybrid/charging warning
- No READY, electric drive or charging unavailable
- Start-stop inoperative (mild hybrid)
- 12 V battery drained
- Likely causes
- LikelyBattery module software or calibration fault (update released)
- PossibleModule fails to wake up in extreme cold or after a 12 V dip
- PossibleDamaged CAN lines or connector at the battery pack
- RareBattery energy control module internally faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €80 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.