What does code U0642 mean?

DTC codes / U06xx · Network communication / U0642

U0642Lost Communication With EVAP System Pressure Sensor/Switch Circuit B

U0642 is a network communication code indicating that a control module on the vehicle's Controller Area Network (CAN) bus has stopped receiving valid messages from the evaporative emission (EVAP) system pressure sensor or switch circuit. The module that set the code detected a loss of the periodic data message it expects from that sensor or its dedicated control circuit, not necessarily a failure of the sensor itself.

SystemNetwork

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaNetwork communication

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