Mechanics

OVERHEATING

1994 Toyota Corolla

Engine Cooling problem
1994 Toyota Corolla 4 cyl Front Wheel Drive Automatic 153000 miles

My car temperature used to always stay around the half way mark on the temperature guage. Now it keeps rising to close to the red. I noticed that the electric cooling fan is not coming on. I bridged the terminals on the relay that switches on the fan, now it runs constantly. This seems to help, although the temperature guage tends to occasionally rise above the " normal position" I've tried replacing the relay in the fuse box, but the fan still does not turn on automatically.
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Chrisp83
April 3, 2008.




There is a thermal switch that turns the fans on, check this, and make sure the thermostat is working and the radiator has a good flow rate, re post if you have trouble locating the thermo switch,

Mark (mhpautos)
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Mhpautos
Apr 4, 2008.
Thanks for the info. Where would I find the thermoswitch?

Tiny
Chrisp83
Apr 4, 2008.
Hi there,

I will see if I can post a pic for you. But from memory they are near the thermostat on that model will check it out.

Mark (mhoautos)

Mhpautos
Apr 4, 2008.
By " THEY" do you mean there is more than one?

I noticed 2 switches that I suspect could be the thermoswitch.

First is located on the thermostat housing and has one wire coming out of it.

Second one is mounted in the actual engine block and has 2 wires connected to it.

Tiny
Chrisp83
Apr 4, 2008.
Hi there,

The switch with the single wire will be the temp gauge sender. The other should be the thermo fan switch

Mark (mhpautos)

Mhpautos
Apr 4, 2008.
If you disconnect the fan switch, the fans should run all the time. If they do not, then it would be a relay.

Another thing to check is to turn on the AC, the fans should run at a lower speed, if they do not then again it is one of the fan relays or the main engine relay.

Mmprince4000
Apr 5, 2008.

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