U01A3Lost Communication With Hybrid/EV Battery Interface Control Module D
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- U01A3 marks a lost link to battery interface control module D. Before this generic block existed, GM used proprietary numbers for the same fault: the GM U-code list published for the 2011 Saab 9-4X names U2603 to U2606 as the battery energy control module losing hybrid battery interface modules 1 to 4. GM's 2018 hybrid table still groups these older numbers together with U01A0-U01AC and U179C in one fault bundle, so scan reports from different model years may show either form for the same board. In GM's 2016-2019 plug-in tables D is the fourth of eight boards and is rated Type A. One oddity to keep in mind: invalid data from module D is reported as U02A0, outside the U04A row used by its siblings.
- What you may notice
- MIL and hybrid/EV warning (GM Type A)
- Limited power, electric range shortened
- Cell voltages of one pack section shown as unavailable
- Likely causes
- LikelyChain connection from module C to module D interrupted
- PossibleBattery interface control module D defective
- RareScan tool or software generation reports the board under the older GM number
- 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.