U0340Software Incompatibility With Hybrid/EV Battery Interface Control Module G
- Generic OBD-II code · Network
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- G is the seventh board, a position GM's 2016–2019 plug-in hybrids really have: table 16OBDG02 describes eight interface modules on a UART daisy chain to the battery system module. That table publishes lost-contact and processor tests for every board, yet it holds no counterpart to the P1EB1 version check of the older VITM design and no U0340. For G, GM thus documents silence (U01A6), not a software conflict. The older four-board design is stricter: P1F06 to P1F09 make each slave return a key value computed by a seed-and-key algorithm and fail it when wrong values persist for 1 s within a 1.4 s window, Type B in the 2015 table. U04A7 is the invalid-data code for G.
- What you may notice
- Hybrid warning, MIL possible depending on the maker
- Electric mode limited or unavailable
- Other battery diagnostics paused while the code is active
- Likely causes
- LikelySeventh board replaced by a unit with another software level
- PossibleBattery system module reflashed without the boards being brought along
- RareDisturbed daisy-chain link garbles the version data of board G
- Inspection (ITP)
- Can matter for the ITP: it concerns the emissions system.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.