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2016 Climate Control Issues

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by Daykray, Jan 12, 2020.

  1. Daykray

    Daykray New Member

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    2016 Prius
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    Four
    I have a 2016 Prius IV with some very odd climate control issues. Up until about a few weeks ago the climate control worked normally. It came on immediately when starting the car to the last preset and worked as it should. Now the climate control takes about a minute to show anything on the screen and allow me to change any settings. When it turns on it seems to start at a default state with the "Auto" button on and the AC turned on. The heat also starts out at the same set temp every time it turns on no matter the last preset. While driving the heat is very hot and only cools down when stopped even when lowered to the lowest heat setting. After bringing it to the dealer to diagnose, they told me the climate control head unit would need to be replaced which I have done and I still yield the same odd issues. Has anyone else had these issues or have any insight? Any help is appreciated.

    Thanks!
     
  2. FuelMiser

    FuelMiser Senior Member

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    Check your 12V aux battery!
     
  3. Daykray

    Daykray New Member

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    Can you expand on how the 12v battery causes this issue?
     
    #3 Daykray, Jan 13, 2020
    Last edited: Jan 13, 2020
  4. Daykray

    Daykray New Member

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    Can you expand on how the 12v battery causes this issue?
     
  5. Hidyho

    Hidyho Senior Member

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    The 12V aux battery is in charge of keeping everything going while the car is off, it is the battery for all the electronics, if its going bad, the electronics could be losing memory.

    Most Hybrid vehicles such as the Toyota Prius feature a conventional 12 Volt auxiliary battery in addition to the high voltage hybrid system battery.

    The 12 Volt battery is not used for engine starting or to power the traction motors but is used to supply power to:

    Accessory systems
    Headlights
    Audio systems
    Computer controls

    The 12V is charged up by the traction battery in running mode, but it is a 12V battery and can go bad after so much use or age, causing problems, thus have it checked or replace it due to age if you want.
     
    FuelMiser likes this.
  6. Daykray

    Daykray New Member

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    Four
    I will totally check the battery out. Thanks!

    Could this lead to the issue of the heat not cooling down while driving? While driving even if I lower the temps the heat doesn't change or get cooler. Even when I turn the AC on. It only cools down when I'm stopped.