What does code U0240 mean?

Q: What does code U0240 mean?

Lost Communication With Entrapment Control Module B. U0240 is a generic network communication code indicating that a primary control module has lost contact with the entrapment control module B, which is typically responsible for power window, sunroof, or liftgate anti-pinch safety functions. The computer detected a failure of the module to respond to periodic status messages over the vehicle's communication bus, often setting the code after multiple missed heartbeats.

DTC codes / U02xx · Lost communication with a control module / U0240

U0240Lost Communication With Entrapment Control Module B

U0240 is a generic network communication code indicating that a primary control module has lost contact with the entrapment control module B, which is typically responsible for power window, sunroof, or liftgate anti-pinch safety functions. The computer detected a failure of the module to respond to periodic status messages over the vehicle's communication bus, often setting the code after multiple missed heartbeats.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaLost communication with a control module

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.