AI DamageU18A2 code in owner complaints
Code U18A2 is named in 10 US owner complaints. Models: 6, model years 2017–2022.
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 U18A2: the letter U means network communication between modules; the second digit 1 marks a manufacturer code whose meaning is set by the make; the last three characters 8A2 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
- 10
- Models
- 6
- Model years
- 2017–2022
Which models and years
Models whose owners name this code (6). 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.
Service engine soon light. U18A2 code sent to Onstar. Inspected and confirmed by dealer. Vehicle is currently sitting at dealer that I purchased it from and out of service until repaired.
Code U18A2 (lost communication with fuel pump communication module), part is available for inspection, we were all at risk due to the car stalling on the highway with no prior warnings, check engine light came on after car stalled, ordered new part from GMC, fix the issue right away.
I know someone with a code reader device that I asked to come hook up to my car and read what code was causing my check engine light to pop up. The reader displayed the code U18A2 which indicates a "Lost Communication with Fuel Pump Control Module (FPCM)".
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.