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No heat after replacing coolant control valve

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by lastradakiwi, Oct 27, 2024.

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  1. lastradakiwi

    lastradakiwi New Member

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    2017 Prius c
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    One
    I replaced the coolant control valve in my 2009 Prius today! It was a bit challenging since this was my first time doing any major work under the hood, but I managed to get it done. The strange noise I heard before that I posted before is now gone, which is a big relief! Here's a link to it if you're curious: Weird rotating noise near driver area | PriusChat

    Since a lot of coolant leaked out during the process, I went to Walmart and picked up this product: SUPER TECH AFC ASIAN RED 5050 PREDILUTED 1-GAL - Walmart.com. I followed the coolant top-up steps from this YouTube video:

    .

    The car is running smoothly now, but the only problem is that I no longer have heat, even though the heater was working fine before!! I made sure to follow all the steps carefully, and there are no warning lights on the dashboard.

    Does anyone have any ideas about what might be going on?
     
    #1 lastradakiwi, Oct 27, 2024
  2. Brian1954

    Brian1954 Senior Member

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    Check the coolant in the radiator. Remove the metal radiator cap and make sure the coolant is filled to the very top. They did not do that in the video that you linked to.
     
    #2 Brian1954, Oct 27, 2024
  3. JC91006

    JC91006 Senior Member

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    If you drained all the coolant before you started, hopefully you still have it and can measure how much came out. I just did this recently and I needed 2 gallons of coolant to fill it back up.

    In your case, bleeding this car is quite difficult so you'll have to check the radiator every morning to make sure it's full (morning because that's when the car is cold). Add until it's full and check again the next day. Repeat until it no longer needs coolant. Your heat should return once it's full of coolant
     
    #3 JC91006, Oct 27, 2024
    SFO and Brian1954 like this.
  4. saneesh8

    saneesh8 Junior Member

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    I had to do the coolant refill procedure recently. Replaced the water pump and thermostat as preventive maintenance. Used 2 gallons of genuine Toyota coolant. Did the bleeding with the screw and with the coolant storage tank procedure. Still there was air left in the system.

    I think you already squeezed out the bubbles as much as you can. Now drive with heat on and refill the radiator and reservoir after few days of driving. Just like @JC91006 suggested. Also the valve is replaced correctly?

    Try to use the Toyota coolant. It is not expensive and get 2 jugs. Mixing coolants of different types can give bad results. It can clog the tiny passages.
     
    #4 saneesh8, Oct 28, 2024
  5. lastradakiwi

    lastradakiwi New Member

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    Thanks everyone! I refilled the radiator coolant and my heat works again.
     
    #5 lastradakiwi, Oct 28, 2024
    Brian1954 likes this.
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