U01A7Lost Communication With Hybrid/EV Battery Interface Control Module H
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- U01A7 refers to battery interface control module H. On packs with exactly eight boards it is the tail of the chain: the GM plug-in hybrid tables for 2016 to 2019 stop at U01A7, and both Audi bulletins (A3 Sportback e-tron 2016, Q5 e 2022 and 2024) list precisely U01A000 to U01A700. Since the master always names the first board it cannot reach, H on its own excludes a break further up; the cause sits in H itself, its supply or the final link leading to it. A fault earlier in the chain shows up as a lower letter, even though H then falls silent as well. GM's 2016 table requires 5 s above 10.2 V and rates the fault Type A, so the MIL lights on the first trip; 2018 to 2019 the time is 4.5 s.
- What you may notice
- MIL on the first trip (GM Type A)
- Electrical system or hybrid warning, power reduced
- All other module letters report normally
- Likely causes
- LikelyFinal chain link from module G to module H interrupted
- PossibleBattery interface control module H defective
- RareTermination or return line at the end of the chain faulty
- 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: €100 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.