U01B2Lost Communication With Planetary Gear Set Control Module
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Hybrid transmissions such as the two-mode system developed by GM, Daimler, Chrysler and BMW use two or three planetary gear sets plus clutches to switch between power-split and fixed-ratio operation. A planetary gear set control module would run those shift elements and report their state to the hybrid or transmission controller. U01B2 means this module has gone off the network, so the controller no longer knows which gear-set state is engaged. No manufacturer documents the code publicly. CARB 1968.2 counts transmission and hybrid control units among the monitored powertrain parts, so a MIL is likely wherever the code is used. Expect a hybrid system warning together with reduced power or a limited fallback mode; U04B3 covers implausible data from the same module.
- What you may notice
- Hybrid system warning
- Reduced power or limited fallback mode
- MIL on
- Likely causes
- LikelyDamaged CAN wiring or connector at the transmission
- PossibleModule without supply voltage or ground
- RarePlanetary gear set control module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.