U064BLost Communication With Hybrid/EV Battery Pack Current Sensor B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Some packs carry a second current sensor, B, often a different measuring principle than A, so that the battery controller can cross-check the two through P0B13 and still have a value if one fails. U064B is stored when that second digital sensor goes silent. No manufacturer publishes U064B. With only one remaining sensor the controller loses its redundancy; depending on the safety concept it may keep driving with sensor A but flag the fault, or reduce power until the plausibility check can run again. Sensors like LEM's CAB family send their readings as periodic CAN frames, so a missing frame stands out quickly. Section (e)(15.2.3)(A)(iv) of the CARB rule covers this input as well. An analog sensor B would instead log circuit faults P0B0E to P0B12.
- What you may notice
- Battery system warning lamp
- Correlation check between the current sensors no longer possible
- Possibly reduced charging or drive power
- Likely causes
- PossibleBus or supply wiring of sensor B damaged
- PossibleCurrent sensor B failed
- RareMissing or faulty CAN termination in the pack sub-network
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €150 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.