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HVAC control panel acting weird

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by trentofdestiny, Jul 15, 2019.

  1. trentofdestiny

    trentofdestiny Master Finagler

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    Today when I left work the HVAC was off from my trip to work. I pressed the auto button and maybe slipped and hit the recirc button at the same time. All the LCD segments came on and started flashing. Then it read 00 degrees. I had to turn the car off and back on to make it work. I could not reproduce it again by hitting two buttons at the same time. What was going on? Was it a self test mode? It was 90 degrees out today, which is pretty hot, even for here.
     
  2. ChapmanF

    ChapmanF Senior Member

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    AUTO + RECIRC together (usually right when you are powering the car on) is exactly the combo to get the HVAC diags.
     
  3. trentofdestiny

    trentofdestiny Master Finagler

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    But the car was already on for a few seconds before I tried to activate the HVAC. And I couldn't reproduce it but just tapping the buttons.


    iPhone ?
     
  4. ChapmanF

    ChapmanF Senior Member

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    Just went out and tried it on mine. Seems to work if the two buttons are pressed any time within five seconds or so after powering the car on.
     
  5. trentofdestiny

    trentofdestiny Master Finagler

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    I see. I will try it tomorrow as my car is outside rather than in the garage. Good to know though. Thanks! Does it exit the mode on its own?


    iPhone ?
     
  6. ChapmanF

    ChapmanF Senior Member

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    When you power the car off, or press the HVAC off button.