The Ventilation Fan and Electrically Heated Rear Window Do Not Start Until 20 S After the Ignition Has Been Turned on

The Ventilation Fan And Electrically Heated Rear Window Do Not Start Until 20 S After The Ignition Has Been Turned On












Fault symptoms
The ventilation fan and electrically heated rear window do not start until 20 s after the ignition has been turned on

Diagnostic help
Ignition +54 can be read in DICE using the diagnostic tool.

If +54 is missing when +15 is present, the bus message Ignition +54 ON will be generated after 20 s.

The ACC uses the bus message Ignition +54 to disengage the ventilation fan while the engine is being started.

Fault Diagnosis Procedure