Network
generic / SAE
U01B3
Lost Communication With Brake Blending Actuator
ECU lost communication with the brake blending actuator (modulates between regen and friction braking on hybrids/EVs).
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number1 / B3
Possible causes
- Actuator unpowered or wiring broken high
- Gateway module routing CAN messages incorrectly low
- CAN terminating resistor (120 Ω) drifted out of spec low
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
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 300–2500 €
- Estimated time: 1–8 h
- Component: brake blending actuator
- Component: can bus
- MIL / check engine light
- drive cycle required
- limp mode possible
Sources
References
sae:J2012