My radiator fan won't turn off on a 97 mercury Tracer.

You're looking for something like this:

Allstar Performance 6 Blade Fans ALL30102

It's usually located at the very front of the engine in front of the radiator. It is located inside a fan shroud.
Allstar Performance Fan Shrouds ALL30114

The fan circulates fresh air into the radiator and engine to help keep it cool.

WARNING: when the engine is running, the fan is rotating (very quickly!), so you most likely will not be able to see it. It is dangerous, so do not stick your hand or anything else into the area when the engine is running.

... How Does Radiator Fan Work DoItYourself com

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"rule out" questions - is coolant level OK? Any leaks, especially around the water pump? Has the system ever been flushed. out? If this is the original radiator, it could be clogged. Is the thermostat installed correctly with spring end toward the engine?

Just to test the fan disconnect at a connector and apply power directly from the battery. If you have 2 wires at the connector on will be earth and the other will be power.. If the fan is free to run and is not burnt out it should spin. If it does then your problem is in either the relay or temp sender unit

sounds like the relay is stuck on

check the clip on bottom of the blower motor, mine was cliped in but contact was lost.

needs a new blower motor or resistor

Have you tried to jump it? Possible bad alternator?

It might be a bad relay or a bad engine coolant temp sensor. Fan is likely good. Might have 2 relays. See owner manual.

The ECU drives a relay which in turn drives the fan. Trace the fan wiring back to the relay and check the plug connection. Does the fan turn freely by hand? If not, replace it. The fan needs a solid ground connection as well as power from the relay.

IWANNA FIX A TIMING BELT