Parking Heater

Activation of the parking heater is selected with a time switch that supplies pin 3 on the Automatic Climate Control (ACC) control module with 12 volts.

The ACC control module sends a 12 volt wake-up signal from pin 4 to the Electronic Display Unit (EDU) control module, which sends information about outside temperature in the form of a sequence of impulses back to pin 18 on the ACC control module.

Provided the ignition is off, this results in the following selections:

Air mixing damper Normal function
Air distributor Normal function
Air recirculation flap 100% recirculation when outside temperature is <-10° C (14° F)
100% fresh air when outside temperature is >-10° C (14° F).
Ventilation fan 5.5 A motor current
Electrically heated rear window and electrically heated door mirrors Off
Rear door fans Off
Display Normal function
LEDs Normal function
Push-buttons All manual selections except "OFF" and control of fan speed are possible.


NOTE : "OFF" cannot be selected while the parking heater is activated. This means that the selection can only be cancelled by cancelling the selection at the timer switch or by switching on the ignition.