1989 Toyota Corolla thermostat/cooling fan?

1989 TOYOTA COROLLA
270,000 MILES • 4 CYL • FWD • MANUAL
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STEWBALLS
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Just recently, when starting my car the main cooling fan starts automatically even if the car has been sitting outside overnight, or just during regular operation. And the fan doesnt stop running until I turn off the ignition. The temperature gauge on the dashboard starts cold and levels out at midway. Essentially the fan just doesnt stop until I turn off the car. Im a novice when it comes to working on my car, but thought I might try and find out what the problem could be. Coolant temperature switch or thermostat, or something else altogether.

Thanks for your time

Stu Vancouver
Dec 12, 2008 at 12:17 AM
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ZACKMAN
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Start with the coolant temp switch and the radiator fan relay.
Dec 12, 2008 at 12:51 AM
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MMPRINCE4000
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To add to what Zackman said:

The fan switch is most likely the problem, it is located on the thermostat housing, and is a single wire white connector.
If the fan switch fails, the fans will run anytime the ign. is on (a backup feature to prevent overheating).
This is also how you test the fans if they do not come on, disconnect the fan switch and if the fans run the fan motor is good, if not then the fan motor, fan relay, fuse, or engine main relay is bad.
Dec 12, 2008 at 7:22 AM
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