U0111
Lost Communication with Battery Energy Control Module A
What it means
The Battery Energy Control Module has stopped transmitting on the vehicle data bus, so other control units no longer receive its messages. High-voltage battery-management data is lost; the hybrid/EV system may disable the drive. Typical causes are loss of power or ground at the module, an open or shorted CAN/LIN bus wire, a connector fault, or an internal module failure.
Is it safe to drive?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
BMS unpowered (12 V supply)
highOne of the most commonly reported causes for this code — check this first.
CAN wiring to BMS broken
mediumA plausible cause — test and verify before replacing parts.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
Related help
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