Pic. 7-41. Scheme of switching on the electric motor of the heater fan and heating elements of the exterior mirrors and rear window:
1 - ignition switch;
2 - mounting block;
3 - heater motor switch;
4 - additional resistor;
5 - heater electric motor;
6 - rear window heating element;
7 - heating element of the exterior mirror;
8 - switch for heating the rear window with a control lamp;
A - to power supplies;
K6 - additional relay;
K7 - relay for turning on the heated rear window.
To obtain different speeds, an additional resistor is used. It is fixed with a screw on the left side of the heater core housing. The resistor has three coils and a fuse. When three spirals are connected to the electric motor power circuit, the 1st fan speed is provided, if two spirals are turned on - the 2nd speed, if one spiral is turned on - the 3rd speed. When the electric motor is turned on without a resistor, the fan rotor rotates at the maximum 3rd speed (3000 min-1).
It is recommended to replace a defective electric motor with a new one. The only possible repair is cleaning the collector. There is no need to remove the electric motor from the vehicle for this. It is enough to remove the water deflector, the protective casing of the electric motor, and then the cover of the electric motor with the brush holder.