AI DamageU2603 code in owner complaints
Code U2603 is named in 11 US owner complaints. Models: 1, model years 2016–2018.
There is little data for this code or its meaning is ambiguous, so this page is not indexed.
What the code means
This is a manufacturer-specific code: the meaning depends on the make and sometimes on the year.
How to read U2603: the letter U means network communication between modules; the second digit 2 marks a manufacturer code whose meaning is set by the make; the last three characters 603 identify the specific fault.
Codes for engine, transmission, transfer case and hybrid system modules. When valuing an auction car the key question is whether the fault is crash related (cut wiring, damaged radiator) or a known defect of the model.
Key figures
- Complaints with this code
- 11
- Models
- 1
- Model years
- 2016–2018
Which models and years
Models whose owners name this code (1). Years link to the model year problems page.
Components named together with the code
Component as the owner filed it (one complaint can list several).
Complaints by model year
What to do if an auction car has this code
- Separate crash damage (wiring, radiator, mounts) from known model defects: see the model year problems page.
What owners report
Excerpts of owner complaints in the original wording. Owner statements not verified by the regulator; personal data removed.
These are the codes is is throwing. B101D p1eoo P1EAC poafa B3111 U3001 U2401 U2603 U2604 U2605 U2606 U2617 U2618 U2619 U2620 U2621 U2622 U2623 U2624 P1FD1 P1FD2 P1FD3 P1FD4
Check Engine light codes U2603-06, U2623, well known issue in chevy volt community, that points to Chevy faulty BECM. Chevy replace these to some selected 2016-2018 vehicles, but they wont cover mine, while I have same exact issue.
As usual they informed that I need a new $10k battery. I did my own research and the error codes (U2603, U2604, U2605, U2606, U2617, U2618, U2619, U2620, U2621, U2622, U2623, U2624 and P1E00) clearly indicate that my BECM failed.
Sources: public official US data (owner complaints) and the SAE J2012 standard. Complaints are owner statements not verified by the regulator. A code from a complaint does not replace a scan tool diagnosis. Data updated 2026-11-10.