1990 Corolla Cooling system problems

like all cars with elect fans.
1: stuck relay
2: stuck signal controlling said relay

on older cars the controlling factor is the fan over temp switches
on newer cars the PCM controls all that.
the best way to fix cars is to get the book.
the book is called FSM. factory service manual.

alldata.com

or at toyotanation, dot com.
prizm = corolla.

I am sorry but we have no wiring diagrams here at fixya due to copyrighted material.

You've figured out by now the blinking light means the system has a problem. You'll need to find out if the system is low on freon or if a relay or electrical part is failing. The cooling fan could also be failing to come on, which would make the high side pressure exceed the limit and shut down the system.

its 22 yrs old so without a look under the bonnet i couldnt say but i would suspect a head gasket or the water ports in the corroded away even more so if no antifreeze in the system .but it could be a blocked rad or a cooling fan not working a thermostat jammed in fact anything so ask the opinion of a local mechanic first before listerning to any old tom **** or harry who after one beer know a bit and after three beers know everything their is to know about motor vehicle technology

Try to check the temperature switch

you've got a possible blockage in the head or block.

head gasket failure & or warped head
Get it fixed asasp!!!

Follow the lower radiator hose to the engine. Most Toyota's along this year model have the thermostat located in the engine, where the lower radiator hose connects to the engine. Changing the thermostat is pretty straight forward. Refilling is a little trickier. Search the top of the engine and find the bleeder screw for the cooling system. Open this bleeder screw, usually a 10mm, or 12mm socket will fit, and fill the cooling system with the recommended coolant. Pay attention to your mixing ratio as well.

Are U sore, that U must use freon in your cooling system?
I think the system use R 134 gas for cooling, with a special climate compressor oil.

The corolla fans are pretty standard over this period. Verify that the electrical connector is identical and you should be good to go.