U3009Control Module Ground B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- U3009 is the counterpart for the second ground path, B. In the GM brake module of 19OBDG03B the same ratio test runs the other way round: if (G1 − G2)/(G1 + G2) drops below −0.9 for 200 ms, ground 2 is judged disconnected, Type A with MIL. Ford's steering module on the 2025–2026 Explorer, Police Interceptor and Aviator shows that B is a different physical point: TSB 26-2150 sends U3009:1B to the right-hand shock tower ground, G103 on the Explorer and G119 on the Aviator, while ground A sits on the frame rail, and the repair there renews the fastening. Because one good ground can carry the module for a while, the fault may come and go with load, heat or moisture. If both U3008 and U3009 appear, check the shared ground circuit and the battery negative first.
- What you may notice
- Intermittent steering assist or brake warning messages
- Heavier steering or reduced brake control while the fault is active
- Likely causes
- LikelyLoose nut or stud at the ground B mounting point
- PossibleCorroded contact face at the strut tower or body ground
- RareDamaged ground wire B or crimp in the harness
- Repair
- Medium · Often possible to do yourself.Typical cost: €10 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.