U040EInvalid Data Received From Turbocharger/Supercharger 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
- U040E is reserved for a second charger control module, B, on engines that run two separately actuated chargers: twin or sequential turbo layouts, or a turbocharger combined with an electrically driven or clutched supercharger. The engine controller sets it when module B's position or status messages keep coming but are judged invalid. No manufacturer documents U040E publicly, the NHTSA bulletin index has no entry, and thresholds are unknown. A useful check in the workshop is whether U040D is also stored: if only B is affected, its own actuator, connector and line are the first suspects, whereas both together point to the shared bus or the controller. With one charger unverified, boost and torque are usually limited and a MIL is likely, as CARB treats boost control as emission-relevant. U010D is lost contact, U040D module A.
- What you may notice
- Check engine light
- Reduced power, especially at higher load
- Likely causes
- PossibleElectronics or position feedback of charger actuator B faulty
- PossibleConnector or bus line of module B damaged by heat
- RareModule B with software that does not match the engine controller
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.