Electric fan doesn't work
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Borat Impersonator
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Borat Impersonator
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From: St Augustine, FL
Electric fan doesn't work
I found out today that my electric fan does not work. I removed the belt driven fan and the A/C compressor, A/C lines, condenser & fan. I mounted a new high output 2300 CFM fan and plugged it right in to the old connector. I made sure that it moves air the right way by connecting a 12v source (battery). Point is the fan does not turn on and the engine starts to overheat! NOT GOOD. The temp guage was barely over the half way mark and it started running rough, so I shut it down. Where is the temp switch that control this fan? In the wiring diagrams it is shown wired with the temp switch for the A/C, which is probably disconnected. Am I better of wiring the fan to new ground & hot wires and then wire in a manual switch I can control? I know of two coolant related electrical connections on the crossover between the cyl heads, one for the cold start valve and one is the coolant level sender. Is there another coolant temp sensor somewhere? Thanks!
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From: DFW Texas
On the S4 and later cars the four inputs that control the fan are the AC press switch (receiver drier), the coolant temp sensor (RH side low on the radiator), the intake manifold temp input, and the hood ajar switch. On 87-91 with ignition on or engine running the fans will still operate with the hood up. The hood switch kills the fans if they’re running due to the intake temp switch and/or radiator temp switch with the ignition OFF. This safety feature keeps someone from getting hit by the fans if they come on with the ignition off. With the switch on or engine on this feature is disabled since you should know the fans could run in this condition. The temp switch at the bottom of the radiator controls the operation of the fan and has a fail closed position. If the switch failed open it would cause over heating. You can check by pulling the wires off the switch and measuring it with a VOM. This is the big round one in the front RH lower side; it’s hard to get to.
I don't know if it's the same for your 80MY????
Hope this helps. Also, If it were my car I wouldn't use a manual switch that I had to remember to turn on. Someday someone else will be driving the car and ruin YOUR engine.
Jim Mayzurk
93 GTS
I don't know if it's the same for your 80MY????
Hope this helps. Also, If it were my car I wouldn't use a manual switch that I had to remember to turn on. Someday someone else will be driving the car and ruin YOUR engine.
Jim Mayzurk
93 GTS
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From: Ball Ground, GA
There is a temp switch mounted in the lower forward face of the left radiator tank that controls the fan due to coolant temp.
The switch should be open when the coolant is cool, closed when the coolant is hot. We sell a lower-temp switch (as do the other vendors) - Radiator - Fan SWITCH 75C 77-86 823.959.481.F75 $6.84
The refrigerant switch is temp controlled up thru '86, pressure controlled '87 and up. The temp switch doesn't work too well.
The switch should be open when the coolant is cool, closed when the coolant is hot. We sell a lower-temp switch (as do the other vendors) - Radiator - Fan SWITCH 75C 77-86 823.959.481.F75 $6.84
The refrigerant switch is temp controlled up thru '86, pressure controlled '87 and up. The temp switch doesn't work too well.
