U046DInvalid Data Received From Fuel Pump Control Module B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- U046D is about module B, the second of two fuel pump drivers, used on vehicles with two in-tank pumps or a saddle tank; for module A the matching code is U0410. A receiver, normally the engine controller, logs it when the module's reports, such as delivered pump output or its own fault status, arrive corrupt or implausible. No manufacturer documents U046D publicly. Ford shows that the same exchange can be judged without a U-code: in its 2024 OBD summary the pump B driver answers the engine controller over a duty-cycle feedback line, where 20 % (±4 %) flags an invalid command (P027B), 30 % an internal driver error (P26EA) and 0 or 100 % missing feedback, U016C, judged over 2-5 s with an 11-16 V supply. CARB requires fuel system components to be monitored. Expect the MIL, hesitation under load, hard starting or reduced power.
- What you may notice
- Check engine lamp on
- Hesitation or power loss under heavy load
- Long cranking or stalling
- Likely causes
- LikelyPoor ground or corroded connector at the second fuel pump driver
- PossibleDamaged feedback or bus wiring between pump module B and the engine controller
- PossibleWorn pump B drawing excess current and upsetting the driver's reports
- RareInternal fault in fuel pump control module B
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.