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Ignition Output Signal: Description and Operation



Diagnosis of Engine Off Timer

General description
The ECU received the engine off time from the instrument cluster.

Monitor strategy
The diagnosis runs during ignition on.
The ECU is waiting for a time changing after a specified time. A fault will be set if there is no time changing and an engine start followed without an ignition off.

Monitoring conditions for engine off timer
- no engine off timer overflow
- no CAN timeout
- no power fail at the instrument cluster
- battery voltage high enough for CAN communication