Functional Description

Functional Description

Fan:

The climate control fan Q1 is supplied with battery voltage through the key-operated services relay I35 - located in fusebox G1 -; in addition to the relay the supply line also crosses fuse F13 of fusebox G1.

In the versions with fusebox "B" downstream of fuse F13, there is also a special relay I78 which controls the fan Q1 with a supply protected by fuse G255 (30A).

The fan motor Q1 is operated with an earth signal leading from the control knob Q4. This signal crosses the speed regulator Q5, formed of three resistances in series and the crossing of them determines the four different speeds, depending on the signal leading from the knob Q4.

First fan speed, with the compressor engaged:

With control Q4 in position "0" the fan Q1 is stationary but it is operated at first speed if the compressor is enagged: in this case a special relay Q69 controls the fan supply at first speed.

Recirculation

The recirculation function is made by operating the motor Q27, controlled by two switches Q73a and Q73b according to the following logic: through the switch on Q68 the two switches Q73a and Q73b are energised which switch respective positive and earth to the motor making it turn in one direction: if they are de-energised they switch the opposite positive and earth making the port turn in the opposite direction.

Lighting controls:

The lights F8, inside the control panel are supplied by the sidelights circuit - connector D of fusebox G1.

In fact this relay receives the "key-operated" supply - via fuse F17 of G1 box "A" (F15 for box "C") is energised by the same earth signal that controls engagement of the compressor (switch Q68) and sends a signal to the regulator Q5 in correspondence of the 1st speed.