90 Corolla 1.6 Liter radiator fan

Merry Christmas guys…the radiator fan runs always with key on. Since it is driven only up to 10- 15 miles and Honolulu is warm I haven’t been too diligent in finding the problem. Will it wear the fan motor out prematurely (110 K on engine) ? …Thank you, Mike

“Will it wear the fan motor out prematurely (110 K on engine) ?”

If you’re using air conditioning most of the time, then no.

The Air Con is not in use - belt off

Either the coolant temp sensor for the fan is defective or the relay for the fan is defective.

Tester

Thanks Tester…How’s the music coming along ?..hope you see my VVTi solenoid question…these engines are getting too complex…Happy new year…

"The Air Con is not in use - belt off "

Double check that the Air Con button on the dash is not ON.

My Corolla probably has the same engine as yours, your car has a 4afe engine right? (If you don’t know, it is usually posted in big letters on the emissions decal on the underside of the hood.)

I’ve had the radiator fan stop working on my Corolla a couple times, sometimes it won’t turn off, sometime it won’t turn on, at least not reliably. For the first problem, the wiring harness was the problem. Battery acid had eaten away a splice. For the second the radiator fan coolant sensor was defective. I expect this is your problem.

Trying to purchase that part can be problematic, as the parts store computer will show several parts matching that name, and they sort of look the same. Bring the old part to the store, and make sure the part you remove is used for the cooling fan. There’s a similar part for the computer to sense the coolant temperature, and another part that is used by the cold start injector. The way you know it is for the cooling fan, at least when it is working, is if you remove the connector and the coolant is cold, the fan will turn on.

I suspect a short in the wiring harness on my '87 1.6l Nova, making the fans run all the time. I figure that because grounding the temperature switch doesn’t turn them off, and pulling all the fan relays doesn’t turn them off either, which I finally came to figure should have stopped them no matter what.

Not sure how this will help someone from December 2014.

Kind of like feedback on the thread since mine sounds a lot like a similar example.