U0344Software Incompatibility With Hybrid/EV Battery Interface Control Module K
- Generic OBD-II code · Network
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Eleven boards or more are found in GM's Ultium packs: according to Wikipedia the Cadillac Lyriq carries twelve modules and the Hummer EV two layers of twelve, and the battery management works wirelessly. GM's service update N232401570 of October 2025 shows that master software decides whether such a unit is accepted: on 2023–2024 Lyriq and BrightDrop, 2024 Blazer EV and Silverado EV and 2022–2024 Hummer EV, the battery energy control module could stay stuck in its start-up commissioning because one cell monitoring unit was offline. The fix is a reprogrammed control module, by the dealer or over the air, without parts. GM does not say which codes appear. U01AA and U04AB cover K's silence and bad data.
- What you may notice
- Vehicle does not become ready after switching on
- Battery or propulsion warning
- Charging may be refused
- Likely causes
- LikelyBattery controller software does not accept the monitoring unit
- PossibleReleased software update for the battery controller not yet installed
- RareMonitoring unit K replaced and not registered
- Inspection (ITP)
- Can matter for the ITP: it concerns the emissions system.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €0 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.