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If anyone needs a cooling fan switch, you can get one at a reasonable price at Rock Auto right now.
I bought one for my friend Sam's 91 Festiva, put it in today and it works good.
Got it for $8.64 shipped to my house. This is a very reasonable price.
What the switch does:
When the temperature sensed by the switch in the water stream in the thermostat housing is below 207F (97c) the switch is closed and a ground is supplied to the cooling fan relay. So when you turn on the ignition 12v power is supplied to the relay (also to the fan motor), this causes the relay to open the spring activated ground connection in the relay to the cooling fan motor preventing the fan from running. When the fan switch senses a temperature of 207F or greater, the the cooling fan switch opens to eliminate the ground to the relay and this in turn cuts the current to the relay that was holding the spring activated ground circuit for the cooling fan open..so the fan comes on.
If you want your cooling fan to run all the time, simply remove the wire from the cooling fan switch and it will remove the power to the fan relay that was holding the ground switch open.
If you have AC, turning on the AC switch will also break the ground to the cooling fan relay and your cooling fan will run as long as your AC is on, unless the temperate of the water in the thermostat housing is greater than 207F in which case the fan will continue to run after you turn off the AC until the temperature falls below 207F.
If your cooling fan switch is not working correctly and is always providing a ground to the cooling fan relay no matter what the sensed water temperature, you cooling fan would never come on. Also you switch could not be working the opposite way and thus never providing a ground, in which case your fan would always run anytime your ignition was on.
I bought one for my friend Sam's 91 Festiva, put it in today and it works good.
Got it for $8.64 shipped to my house. This is a very reasonable price.
What the switch does:
When the temperature sensed by the switch in the water stream in the thermostat housing is below 207F (97c) the switch is closed and a ground is supplied to the cooling fan relay. So when you turn on the ignition 12v power is supplied to the relay (also to the fan motor), this causes the relay to open the spring activated ground connection in the relay to the cooling fan motor preventing the fan from running. When the fan switch senses a temperature of 207F or greater, the the cooling fan switch opens to eliminate the ground to the relay and this in turn cuts the current to the relay that was holding the spring activated ground circuit for the cooling fan open..so the fan comes on.
If you want your cooling fan to run all the time, simply remove the wire from the cooling fan switch and it will remove the power to the fan relay that was holding the ground switch open.
If you have AC, turning on the AC switch will also break the ground to the cooling fan relay and your cooling fan will run as long as your AC is on, unless the temperate of the water in the thermostat housing is greater than 207F in which case the fan will continue to run after you turn off the AC until the temperature falls below 207F.
If your cooling fan switch is not working correctly and is always providing a ground to the cooling fan relay no matter what the sensed water temperature, you cooling fan would never come on. Also you switch could not be working the opposite way and thus never providing a ground, in which case your fan would always run anytime your ignition was on.