What does code U300E mean?

Q: What does code U300E mean?

Ignition Input On. U300E is a generic control module code indicating that a module has detected the ignition input circuit in the 'On' position when the module expected a different state, typically during a commanded power mode transition. The computer is not reporting a sensor failure but rather a mismatch between the ignition switch signal it receives and the power mode it commands or expects.

DTC codes / U30xx · Network wiring and bus faults / U300E

U300EIgnition Input On

U300E is a generic control module code indicating that a module has detected the ignition input circuit in the 'On' position when the module expected a different state, typically during a commanded power mode transition. The computer is not reporting a sensor failure but rather a mismatch between the ignition switch signal it receives and the power mode it commands or expects.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

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.