GF67.29-P-0003TX Heated Rear Window, Function

GF67.29-P-0003TX Heated Rear Window, Function

Component Identification:

Function requirements:
^ Circuit 15 ON
^ No undervoltage or overvoltage

Function
When the heated rear window switch on the AAC control and operating unit or the comfort AAC control and operating unit is pressed, the heated rear window is switched on by the rear SAM control module. This is indicated by function LED in the heated rear window switch. Pressing again cancels the function. Simultaneously the function LED in the heated rear window switch goes out.
The rear SAM control module determines if and how long the heated rear window is to be switched on. The time control (0 to 20 minutes) depends on the outside temperature, the interior temperature and the vehicle speed
The vehicle speed is relayed by the instrument cluster via CAN-B

The outside temperature (sensed by the outside temperature indicator temperature sensor) is transmitted to the CAN-B bus via the driver-side SAM control module. The interior temperature (sensed by the interior air temperature sensor) is transmitted to the rear SAM control module by the overhead control panel control module via CAN-B bus.

Undervoltage or overvoltage
The vehicle electrical voltage is read in via the EIS control module and is relayed to the rear SAM control module via CAN-B bus. If overvoltage or undervoltage is recognized during the heating phase, the heater rear window is switched off and the function LED in the heated rear window switch starts to flash.
When the voltage returns to the specified value, the function is continued and the function LED illuminates continuously. In the event of excessive undervoltage or overvoltage, the heated rear window is switched off completely.