3315602 - E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING - Functional description

Functional description

The heated rear window relay J55 controls the simultaneous switching on of the demisting function of the rear window P55 , the heated windscreen P56 and the external rearview mirrors P60 and P61 . (The control circuit of the heated rear window P55 passes through the power source/amplifier aerial P25 -  See E3510  RADIO ) The supply line to the latter is also protected by the mirror demister fuse B16 . The relay J55 is supplied by the direct line from the battery through the fuse B33 . An earth signal from the electronic Check device M45 - pin 10 of connector C - energizes the coil of relay J55 , so supply is sent to the resistors of P55 , P56 , P60 and P61 : this signal is enabled and suitably time-lagged by the device M45 . An ignition-operated power supply (INT/A) for the Check device M45 reaches pin 9 of connector C through fuse F1 of junction unit B1 : pin 7 of connector C is earthed. The device M45 gives enablement to the time-lagged switching on of the rear window when it receives the command from the on/off button - pin 11 of connector A - and at the same time the engine rpm signal is present - pin 8 of connector B, coming from the instrument panel E50 . The enablement takes place when the engine speed is above 1000 rpm. The button which switches on the heated rear window function is in the climate control panel H80 : the command is sent to the climate control unit M70 - pin 13 of connector C - from pin 9 through the serial line. The control unit M70 is supplied - to pin 11 of connector B - from the ignition-controlled line (INT/A) of relay R1 protected by fuse F9 of junction unit B1 : pin 8 of connector C is earthed. From pin 9 of connector B of M70 , the command is sent to the Check device M45 - pin 11 of connector A. With the function switched on, the Check device M45 sends back a signal - from pin 2 of connector B - to illuminate the led which indicates that the function is on; the signal reaches pin 11 of connector C of M70 and from there the controls H80 .