What does code U301F mean?

Q: What does code U301F mean?

Control Module Wake-up Circuit B Low. U301F indicates that a control module on the vehicle's network has detected a low-voltage condition on a wake-up circuit, which is the signal line used to rouse another module from sleep mode. The computer sets this code when the wake-up circuit B voltage stays below the expected threshold for longer than the module's programmed delay, preventing reliable communication or activation of the affected module.

DTC codes / U30xx · Network wiring and bus faults / U301F

U301FControl Module Wake-up Circuit B Low

U301F indicates that a control module on the vehicle's network has detected a low-voltage condition on a wake-up circuit, which is the signal line used to rouse another module from sleep mode. The computer sets this code when the wake-up circuit B voltage stays below the expected threshold for longer than the module's programmed delay, preventing reliable communication or activation of the affected module.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaNetwork wiring and bus faults

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