Ventilation Fan and Rear Window Heater Cannot Be Started

Ventilation fan and rear window heater cannot be started before 20 s after ignition on












Fault symptom
Ventilation fan and rear window heater cannot be started before 20 s after ignition on.


Diagnostic help
Ignition +54 can be checked in DICE using the diagnostics tool.
If +54 is absent when +15 is present, bus message Ignition +54 ON after 20 seconds will be set.
ACC uses bus message Ignition +54 in order to cut out the ventilation fan when the engine is being started.