U033BSoftware Incompatibility With Hybrid/EV Battery Interface Control Module B
- Generic OBD-II code · Network
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Module B is the second interface board, and on GM's eAssist mild hybrids it is also the last: bulletin PIT5513D lists exactly two, K112A and K112B, for 2016–2018 Silverado and Sierra and the 2018 LaCrosse, both under the same part number 24282084. Since one spare fits either slot, the part number alone does not tell which position a board serves. FCA's 2017–2018 Pacifica Hybrid shows a related split with maker-specific codes P1A29 and P1A2A for cell supervisory circuits A and B; bulletin 08-047-20 clears them by reflashing the battery pack control module. Neither maker documents U033B itself. U01A1 means B is silent, U04A2 that its data are invalid.
- What you may notice
- Hybrid system or battery warning, often with the check engine lamp on PHEVs
- Electric assist or electric driving reduced
- Fault follows work on the battery pack
- Likely causes
- LikelyBoard B replaced with a spare carrying another software level
- PossibleBattery controller software older than the board it has to accept
- RareIdentical boards A and B swapped during pack repair
- Inspection (ITP)
- Can matter for the ITP: it concerns the emissions system.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €60 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.