'99 Buick Regal coolant will cone on.

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2012 Buick Regal Coolant Temperature Sensor

AutoZone https://www.autozone.com > engine-management > 20...

Delphi Coolant Temperature Sensor TS10076 · PRICE: 32.99 · Location:: Coolant Temperature Sensor · Connector Gender: Female · Terminal ...

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It`s a 2000 buick regal ls. make sure when it gets hot eh fans are running. There is a coolant sensor just below the top radiator hose ON THE ENGINE. This sensor tells the fans when to go on when the engine gets hot and also serves as a low coolant sensor. unplug the sensor and replace it. use a open end or box wrench. if your quick you can replace it and only loose a few ounces of coolant. Hope this helps and God Bless :O)

The fans are controlled by the ECM and it uses the ECT sensor for temperature sensing, so if the check engine light isn't on the sensor is not the problem. You need to have an active test run on the fan system to see what code is returned. Have you tried powering up the fans at the relay?

Give me some more information about this problem. May be i can help.

check sensor on reservoir. Unplug connector to sensor to see if light goes out. If yes, replace sensor. If no, wire may be shorted.

You have a short ot ground and it may be in the computer or a relay, if you have an ohm meter I can tell you how to test it. Post here if you have one or can afford to purchase one for $20.00.

First things to check would be fuse(s) at dash & under hood, as well as rad fan relay & possibly coolant temperature sensor.

Did you try jumping the cooling fans with direct power to see if they worked and the fan motor isnt burned out?You can turn the a/c on while running the car and it should turn the fans on even if the car isnt heated up.

The low coolant sensor should be located in the passenger side radiator tank, You need to take it out and clean the sludge off of it for it to work right. Or you can just unplug it and forget about it, the light will go out and it won't cause any problems.

check for a loose connection, could be on the a/c side.. maybe someone pull a wire to change a battery or something check around..