# 2017 Ford Focus ST - Overheat light

**URL:** <https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617>\
**Category:** Maintenance/Repairs\
**Tags:** coolant, ford\
**Created:** [May 7, 2021, 12:53pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617 "2021-05-07T12:53:43Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![DianeTwist](https://avatars.discourse-cdn.com/v4/letter/d/e480ec/32.png) [@DianeTwist](https://community.cartalk.com/u/DianeTwist)\
**Post date:** [May 7, 2021, 12:53pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617/1 "2021-05-07T12:53:44Z")

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When car is sitting still and running after a few minutes the overheat light comes on and states car is overheated but you can turn the car off and back on and the warning light goes off. What is causing this?

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**Author:** ![Purebred](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/purebred/32/46796_2.png) [@Purebred](https://community.cartalk.com/u/Purebred)\
**Post date:** [May 7, 2021, 12:57pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617/2 "2021-05-07T12:57:31Z")

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Have you checked the coolant level?  
Have you had your cooling system serviced? Needs to be done every three years.  
Is the radiator fan running when you get the light?

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**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\
**Post date:** [May 7, 2021, 1:32pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617/3 "2021-05-07T13:32:40Z")

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The fact that the problem occurs so quickly and goes away immediately (no time for any significant cooling off) upon shutting off and restarting leads me to believe the problem is electrical in nature, possibly a faulty coolant temperature sensor.

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**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\
**Post date:** [May 7, 2021, 1:56pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617/4 "2021-05-07T13:56:54Z")

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> [@NYBo](#):
>
> the problem is electrical in nature, possibly a faulty coolant temperature sensor.

+1  
More than likely that is true, but the potential for engine damage if there really is an overheating issue screams-out for a qualified mechanic to check and see the exact cause of the problem.

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**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\
**Post date:** [May 7, 2021, 2:06pm UTC](https://community.cartalk.com/t/2017-ford-focus-st-overheat-light/176617/5 "2021-05-07T14:06:39Z")

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Does the engine fan come on?