Code result
U01BB
Lost Communication With Battery Charger Control Module B
Moderate severity
What it means
ECU lost communication with battery charger control module B (on-board charger for HV battery on plug-in hybrids/EVs).
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
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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