Code result
U01A4
Lost Communication With Hybrid/EV Battery Interface Control Module E
High severity
What it means
ECU lost CAN communication with hybrid/EV HV battery interface module E (BMS slave or cell-monitoring submodule).
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Module unpowered
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
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