I have a toyota yaris 1.0 on 2001 it has a blue i think water temperature light popped up do i need to worry

pop the hood and take a look at the coolant level also take a look if there is any kind of build up at the bottom of the reservoir and you might think about flush out the coolant if u have not done it before it is 7 years old time for a flush

Get the coolant pressure tested,its definitely leaking coolant.You will need to get the coolant running line.
Pressure test will help you to know from where exactly coolant/refrigerant is getting leaked.===========For complete step by step troubleshooting i suggest you to go through the help links mentioned below :----Click the link below :-----

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http://schematicsdiagram.blogspot.com/2012/01/coolant-enters-in-transmission-on.html
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http://whatisbyme.blogspot.in/2012/05/1991-toyota-camry-order-coolant-bypass.html

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http://whatisbyme.blogspot.in/2012/05/2002-toyota-camry-puff-of-blue-or-white.html
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http://technoanswers.blogspot.in/2012/04/1994-toyota-camry-coolant-leak.html
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http://schematicsdiagram.blogspot.in/2012/04/2006-cadillac-dts-coolant-leak-at.html
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http://schematicsdiagram.blogspot.com/2011/12/maf-iat-map-and-coolant-level-sensor.html

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http://schematicsdiagram.blogspot.com/2011/12/gmc-engine-coolant-temperature-ect.html

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http://whoisbyme.blogspot.in/2012/06/loosing-coolant.html

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Coolant temperature sensor dies again and again?

http://schematicsdiagram.blogspot.com/2012/01/coolant-temperature-sensor-dies-again.html

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http://repairhelpcenter.blogspot.in/2012/06/2000-daewoo-lanos-where-to-add-coolant.html

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• Replacing Oldsmobile Engine coolant sensor?

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How to test Engine coolant temperature sensor?
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• Replace Coolant Sensor Module on Oldsmobile?

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These details will help.

Thanks.

That the temperature gauge,you engine is cold,and goes off when the engine is warm and at its optimal performance temperature,now if it goes red when your driving then thats a warning its overheating,

It means the engine is still cold or it hasn't reached the proper temperature due to a faulty engine thermostat.

Check loose connection at battery terminal, alternator belt, and harness.

The blue light stays on till the engine is cold. It goes off when the engine warms up. It is normal phenomena.

That's the coolant temp gauge of the engine, when it's blue it means the engine is cold, if it turns red the engine is overheating, if it stays off after the blue goes out the temperature is normal.

Hi Christine, the blue temp light is telling you that the motor is cold, it will go off once the engine has warmed up, nothing to worry about as it is normal, you will notice that it does not have a temperature gauge like some other cars, that is why they have the light, if the red temp light goes on switch the vehicle off immediately, this is telling you that it is overheating, they are very good cars, my father has one, enjoy :)

LMAO pull the head okay?/ it needs a new! head gasket

Ive worked at a Toyota Dealer for the past 11 years and yes this is normal. Nothing to worry about. Everything is working properly