Network, generic

U0111 Lost Communication With Battery Energy Control Module A

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

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.

Likely causes

Battery module software or calibration fault (update released)
Module fails to wake up in extreme cold or after a 12 V dip
Damaged CAN lines or connector at the battery pack
Battery energy control module internally faulty

Symptoms

  • MIL or service-hybrid/charging warning
  • No READY, electric drive or charging unavailable
  • Start-stop inoperative (mild hybrid)
  • 12 V battery drained

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€80–2,500
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

battery energy control modulecan bus wiring

Related codes

U0112U0312U0412U0293

References: gsi.ext.gm.com, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.