What is this fluid on 2003 toyota prius?


Asked by Mar 26, 2015 at 01:34 PM about the 2003 Toyota Prius

Question type: Maintenance & Repair

I have a 2003 toyota prius, there is a
fluid container located next to hybrid
battery area under hood, trying to
figure out what it is for. It is below the
LOW level. The cap says DENSO on

11 Answers

Does youe under hood even look like this, and what does it say on the cap? Click image

1 people found this helpful.

Yes that is what it looks like

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It says DENSO on cap, and don't open when hot

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I thought I could find something on a Prius Forum. No luck..sorry


Ok, it's just seems weird for it to be an overflow tank since it had a FULL line and LOW line marked on the side... The engine coolant container is over on the left hand side under hood.

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That's why I took if off, had second thoughts. But does it say anything else on cap. Like ":use only XXX fluid "?


No that's all it says on cap

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Well, you can give me a big 'thanks for nothing'...I tried

Best Answer Mark helpful

Thanks for trying!!


Its called INVERTER COOLANT FLUID!! Must be changed every 120K miles. It has to do with your car's A/C and heating and is related to the water pump.

1 people found this helpful.


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