1. Attachments are working again! Check out this thread for more details and to report any other bugs.

2012 V A/C

Discussion in 'Prius v Care, Maintenance and Troubleshooting' started by Lildevil, Jun 24, 2023.

  1. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
    My A/C will blow warm when I come to a stop and idle, after it has been blowing cold. The dealer told me the condenser needed replaced. I disagree. I parked outside and let the car run, it is 84 degrees today, when the engine fans both came on, the vents would blow cold, when the fans shut off, it would blow warm. That tells me that when air is being pulled through the radiator and condenser that the condenser has to be good. The refrigerant is full and new, no leaks. So, my question is, is there a separate relay or switch that tells the fans to turn on for the A/C when at an idle? I know the engine temperature sensor works for engine cooling.
     
    #1 Lildevil, Jun 24, 2023
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,014
    15,615
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    [​IMG]

    When Fan No. 3 relay is energized, you get both fans on low speed. When Fan No. 1 and Fan No. 2 relays are energized together, you get both fans on high speed.

    [​IMG]

    Those are the two intended ways they can operate. Sometimes, in case of a problem, you can have only one fan running, or only one speed, not both.

    The relays are driven, in this generation, directly by outputs from the ECM. The ECM has the engine coolant temperature sensor connected to it, and should also know when the A/C is on, by the A/C amplifier sending it a message to tell it so.

    [​IMG]
     
    #2 ChapmanF, Jun 24, 2023
    Last edited: Jun 24, 2023
    Tim Jones, Lildevil, lech auto air conditionin and 1 other person like this.
  3. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,975
    4,716
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    My experience is both fans come on and stay on with the ac system. The odds are against having a bad relay and still having both fans run at times. The only reasonable hardware scenario is if control of relays 1 and 2 is bad. Or both relays are bad.

    A techstream coolant fan active test would narrow things down.

    Besides the relays, a call for ac can be interrupted by high cooling temp, out of range refrigerant pressure or low hybrid battery voltage.

    A clogged condenser can cause high refrigerant pressure. As can an overcharge or clogged dryer or txv.

    A loss of an ac call would also drop the coolant fan relay power. So it might be
    a chicken or egg thing. Which came first? Techstream status monitoring would help.

    IMG_2224.jpeg IMG_2227.jpeg IMG_2228.jpeg IMG_2230.jpeg
     

    Attached Files:

    #3 rjparker, Jun 24, 2023
    Last edited: Jun 24, 2023
    Tim Jones, Brian1954 and Lildevil like this.
  4. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
     
    #4 Lildevil, Jun 25, 2023
  5. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
    Thank you!
     
    #5 Lildevil, Jun 25, 2023
  6. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
    Thank you!
     
    #6 Lildevil, Jun 25, 2023
  7. Tim Jones

    Tim Jones Senior Member

    Joined:
    Jul 17, 2018
    1,706
    553
    3
    Location:
    SE Texas
    Vehicle:
    2011 Nissan LEAF
    Model:
    ----USA----
    I think I remember some kind of complicated freon charge for the car..... watched a video on it a few years ago. Who did the repairs?
     
    #7 Tim Jones, Jun 29, 2023
  8. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
    A Toyota dealer.
     
    #8 Lildevil, Jun 30, 2023
  9. slow_wagon

    slow_wagon Junior Member

    Joined:
    Feb 8, 2022
    27
    10
    5
    Location:
    Upstate NY, USA
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    Agree with RJ, you need techstream to see what is happening and if any codes are stored.
     
    #9 slow_wagon, Jun 30, 2023
  10. Lildevil

    Lildevil Junior Member

    Joined:
    Oct 25, 2020
    30
    2
    0
    Location:
    Omaha, NE
    Vehicle:
    2012 Prius
    Model:
    V
    Thank you.
     
    #10 Lildevil, Jun 30, 2023
  11. Tim Jones

    Tim Jones Senior Member

    Joined:
    Jul 17, 2018
    1,706
    553
    3
    Location:
    SE Texas
    Vehicle:
    2011 Nissan LEAF
    Model:
    ----USA----
    You can get the cable and a copy of techstream on ebay and maybe amazon..... used to be about $35, service plug on one end and usb on the other
     
    #11 Tim Jones, Jun 30, 2023
(You must log in or sign up to post here.)