199001285 - E3030 DEMISTING REARSCREEN AND REAR VIEW MIRRORS - DESCRIPTION

DESCRIPTION

In the case of poor visibility it is possible to activate the demisting of the rearscreen and the exterior rear view mirrors.The heating resistances for these components absorb a considerable amount of energy and are therefore controlled and, possibly, deactivated after they have been working for a certain length of time: the demisting is subject to a delay timer, managed by the Body Computer, according to the following logic:- ignition-operated, starting excluded (INT/A);- engagement signal coming from the special button in the climate control system control panel.Under these circumstances the resistances remain supplied for a maximum of 20 minutes, then the supply is cut off.The supply is cut off in the following conditions:- Key-off- disengagement signal from the button;- battery voltage below 11.5 V;- after the first 10 minutes of operation if the engine speed is below 960 rpm.With the defrosting on the warning light in the climate control system controls also comes on.The activation timer (20 minutes) is set again each time the button is operated.In specifications with an AUTOMATIC AIR CONDITIONER, the climate control system control unit logic also intervenes with the "MAX-DEF" command in accordance with the logic described previously.The "MAX-DEF" function lasts for 3 minutes starting from when the engine temperature exceeds a certain limit.
the deactivation of the MAX-DEF control only causes the switching off of the heated rear windscreen if the command to switch it on came from the MAX-DEF button; if, on the other hand, the command was given via the heated rear windscreen button, it remains on)
The rear window demister circuit is controlled by the heated rear window relay and protected by a special fuse in the engine compartment control unit. The door mirror demister circuit is protected by another fuse in the engine compartment control unit. Both circuits are controlled by the logic described above directly by the Body Computer.n specifications with an AUTOMATIC AIR CONDITIONER - the control signal is received from the climate control unit via the CAN but is received directly from the climate controls by the Body Computer in specifications with a MANUAL CLIMATE CONTROL SYSTEM.