OBD-II code · Network
U04B1 Invalid Data Received From Battery Monitor Module
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 with U04B1?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyModule internal fault or sensor input drift
- PossibleSoftware version mismatch after replacement
- Less likelyGateway module routing CAN messages incorrectly
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–1.5 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Battery Monitor Module
Related codes
- U04AEInvalid Data Received From Hybrid/EV Battery Interface Control Module N
- U04AFInvalid Data Received From Hybrid/EV Battery Interface Control Module O
- U04B0Invalid Data Received From Hybrid/EV Battery Interface Control Module P
- U04B2Invalid Data Received From Particulate Matter Sensor B
- U04B3Invalid Data Received From Planetary Gear Set Control Module
- U04B4Invalid Data Received From Brake Blending Actuator
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.