Code result
U04B1
Invalid Data Received From Battery Monitor Module
Moderate severity
What it means
A receiving module detected implausible data from the 12-V battery monitor (intelligent battery sensor). Voltage, current or temperature values fail plausibility checks and are rejected; SoC estimation reverts to a default model.
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 internal fault or sensor input drift
highOne of the most commonly reported causes for this code — check this first.
Software version mismatch after replacement
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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