The cooling system fans are driven by two permanent magnet DC motors
The engine management system controller controls the operation of the fans.
The engine cooling system fan motors do not require maintenance.
If they fail, replace them with new ones.
To check the serviceability of the electric motors, use the data in the table. 1.
Data for checking the electric motors of the fans of the engine cooling system
Nominal speed of rotation of the shaft with the electric motor load by the impeller, min -1 - 2600-2800
Current consumption at the specified load and speed, A, no more than 25
The controller controls the relay for turning on the electric fans of the engine cooling system.
The electric fans turn on and off depending on the engine temperature.
The diagram in Figure 2 is given for the ME17.9.71 Niva Chevrolet EURO-5 controller
The electric fans operate in two modes - with maximum performance (parallel connection) and with reduced performance (sequential connection) (Fig. 2).
Reduced performance of electric fans is switched on when the coolant temperature is above 99° C, and also if there are DTOZH fault codes in the controller memory or when the air conditioner is running.
Electric fans are switched on sequentially via an additional relay.
The additional relay is controlled from the controller contact "X1/41".
Reduced performance of electric fans is switched off after the coolant temperature drops below 94° C.
Maximum performance of electric fans is switched on when the coolant temperature is above 101° C, and also at high refrigerant pressure in the line, both with the air conditioner running and not running.
Electric fans are switched on in parallel via an additional relay, the right electric fan relay and the electric fan relay left.
The additional relay is controlled from the "X1/41" contact of the controller.
The right electric fan relay and the left electric fan relay are controlled from the "X1/52" contact of the controller.
The maximum performance of the electric fans is switched off after the coolant temperature drops below 95° C.
If there are active DTOZH fault codes, the electric fans of the cooling system operate until the codes are cleared or the engine is stopped.
Replacing the electric motor
You will need a "10" key.
Disconnect the wire from the "minus" terminal of the battery.
Remove the electric fans together with the casing.
Unscrew the nut and remove the impeller.
Remove the pin from the motor shaft.
Unscrew the three nuts securing the electric motor to the casing.
Remove the wire holder.
Remove the electric motor.
Install the electric motor and impeller in the reverse order of removal.