900 SE Sedan V6-2498cc 2.5L DOHC (1995)
Radiator Cooling Fan Motor: Description and Operation
Radiator Fan
The car may or may not be equipped with a 2-speed radiator fan, depending on the market and variant.
Radiator Fan
Irrespective of the position of the ignition switch, current is supplied to relay 155 via fuse 3.
When the Integrated Central Electronics (ICE) receives information to the effect that the temperature of the engine has risen to about 100 °C it
grounds relay 155, causing it to operate and radiator fan 37 to start.
2-Speed Radiator Fan
The ICE controls relays 155 and 61.
At An Engine Temperature Of About 100 °C
When the ICE receives information to the effect that engine temperature has risen to about 100 °C it grounds relay 155, causing the relay to
operate. The voltage supplied to radiator fan 37 is then reduced via resistor 367.
The Radiator Fan Starts And Runs At Reduced Speed.
At An Engine Temperature Of About 113 °C
When the ICE receives information to the effect that engine temperature has risen to about 113 °C it grounds relay 81, causing the relay to operate.
Radiator fan 37 then receives full voltage via maxi fuse 1 in the main maxi fuse board.
The radiator fan now runs at full speed.
Note: All temperatures are those at the thermostat housing.
ICE
The two pressure switches 419 and 166 in the A/C system provide the ICE with information.
If the pressure in the A/C system is too high or if the engine temperature is too high, the ICE switches on the radiator fan at either low or high
speed.
When engine coolant temperature reaches 126 °C or more, the A/C system is switched OFF.
The ICE also sends signals to the engine management systems informing them that the radiator fans are going to be switched ON or OFF so that
idling speed compensation for the increased/decreased engine load will be obtained.
