Code result
U01B3
Lost Communication With Brake Blending Actuator
High severity
What it means
ECU lost communication with the brake blending actuator (modulates between regen and friction braking on hybrids/EVs).
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
Actuator unpowered or wiring broken
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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