Rear Window Defroster

Rear window defroster (R50)


Function
The rear-window defroster (HHS) is switched on using the button in the operating panel when the ignition key is at position 2 and the engine is running. When the rear-window defroster is switched ON, the indicator lamp in the switch lights up.

On cars with integrated heating / air-conditioning regulation and heating control, the rear-window defroster operates for 12 minutes.

On cars with integrated automatic heating / air conditioning system and temperatures above 50° F (10° C), the rear-window defroster runs for 12 minutes. At temperatures below 50° F (10° C), the rear-window defroster runs for 20 minutes.

During a start, the rear-window defroster function is stopped. The indicator lamp remains ON. The rear-window defroster is switched on 2 seconds after the start.

Note: On cars with integrated automatic heating / air conditioning system, the rear-window defroster and the heated windshield are activated with a single button.

Inputs and outputs
Inputs and outputs for the central body electrical system for the functions:
Inputs
Rear window defroster switch (fixed wiring to central body electrical system in cars without integrated automatic heating / air conditioning system)
Rear window defroster switch (via K bus to central body electrical system in cars with integrated automatic heating / air conditioning system)
Outputs
Rear window defroster element via central body electrical system and relay
The indicator lamp (fixed wiring to central body electrical system in cars without integrated automatic heating / air conditioning system)
The indicator lamp (via K bus to central body electrical system in cars with integrated automatic heating / air conditioning system)