Volvo 240/740/760/780/940/960 1990-1998

Electric Fan Switch

Print

TESTING



The electric fan switch, or thermal switch, can be checked by placing the element in a bucket of water using an ohmmeter. Heat the water to approximately 207°-216°F (97°-102°C) and connect the switch leads to an ohmmeter. The switch should have no continuity until the temperature reaches this level. Let the water cool off below 207°F (97°C) and the switch should lose continuity. If the switch has no continuity at any temperature, replace it.

REMOVAL & INSTALLATION



See Figure 1

The thermal switch is located on the top of the radiator, usually on the passenger side.

  1. Disconnect the negative battery cable.
  2.  
  3. Drain and recycle the engine coolant.
  4.  


CAUTION
Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

  1. Unplug the electrical connector from the switch.
  2.  
  3. Using a suitable size socket or wrench, loosen the switch.
  4.  
  5. Remove the switch by hand.
  6.  

To install:
  1. Install the switch into the radiator, and start the threads by hand.
  2.  
  3. Tighten the switch into the radiator, but take care not to overtighten or you will break the switch or radiator.
  4.  
  5. Plug the electrical connector in.
  6.  
  7. Connect the negative battery cable.
  8.  
  9. Refill the coolant and start the engine.
  10.  
  11. Let the vehicle warm up and check the operation of the fan switch.
  12.  
  13. Check the level of the coolant.
  14.  


CAUTION
Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant.



Click image to see an enlarged view

Fig. Fig. 1: The cooling fan switch is located at the upper corner of the radiator

 
label.common.footer.alt.autozoneLogo