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

AC Compressor & Coolant Pump - connected?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by JoeVR, Apr 12, 2023.

  1. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Hi everyone,

    I have a 2007 Gen 2 Prius - 185k miles.

    A few weeks ago my coolant pump died a horrible death - the hybrid system coolant pump. It fried - smelled like burning wires - and apparently popped some fuses along with it. The car was completely unresponsive, so I had it towed to the dealership and they replaced the pump and some fuses.

    Now that the weather is warmer, I realize now that my AC is no longer working. Could this coolant pump situation have killed my AC compressor? I seem to have enough freon in the system. From reading these forums, I also saw that it could either be the AC Amplifier or the compressor . . . How do I access the AC Amplifier?

    Before I evacuate the freon and replace the AC compressor, is there anything else that I can check after the recent electrical hybrid water pump fiasco? I feel like the two problems may be connected, but then again it's a 185k mile Gen 2 Prius.

    Thank you all.
     
    #1 JoeVR, Apr 12, 2023
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,387
    1,796
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    It's common for the inverter pump to burn up right there where the plug is where the pump plugs to the car's harness very common failure point for the Toyota brand pump or the aftermarkets It smokes that connector burns the what is it called AM2 fuse the red one etc this is a pretty easy fix in the driveway by the way too. But since that's not an issue that's all sorted out now the inverter pump is working your maintaining inverter temperature and your air conditioner isn't working now do you know how long it's not been working and why do you think there's enough gas in it You put the pressure gauge from the can on the low side fat hose and you're reading near 100 lb?
     
    #2 Tombukt2, Apr 13, 2023
  3. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Way before you do any of that, ask the car why it thinks the A/C doesn't work.

    You can do that with a good scan tool, or just by holding the AUTO and FRESH/RECIRC buttons while turning the car on, then reading two-digit codes from the corner of the MFD.
     
    #3 ChapmanF, Apr 13, 2023
    SFO likes this.
  4. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Hi all,

    Thank you all so much for the replies - Here is an update:

    1. I hooked up gauges to the system and it reads the same pressure (87 psi) on both the high and low pressure sides. When I start the car and the compressor kicks on (for a few seconds and it’s kind of buzzy), the pressures don’t change at all.

    2. no matter where I direct the air flow, l still get air blowing out of the far left and right vents. The middle vents are fine and shut off when they need to. The defrost and lower vents work fine, but the side vents are constantly blowing.

    3. I have tried so many times to do the AC diagnostic process (holding AC auto and the Recirc buttons while starting the car) but I get no codes or difference in

    There’s still warm air coming out of the vents. Should I replace the AC compressor or does this sound like something else?

    thank you all so much for any advice or support.
     
    #4 JoeVR, Apr 15, 2023
  5. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Do those buttons have their normal functions? When the car is IG ON, can you switch to auto and switch between fresh and recirc, using those buttons?
     
    #5 ChapmanF, Apr 15, 2023
  6. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Thanks for the quick reply!
    With the ignition on, I realize now that the right side steering wheel buttons do not work (recirculate, front and back defrost)

    however, the LEFT side steering wheel buttons work (temp up/down and AC auto)

    and the touch display works to go to front back defrost and recirc

    Does this help narrow it down a little bit?

    thank you!
     
    #6 JoeVR, Apr 15, 2023
  7. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,387
    1,796
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    It sounds to me like you may have trouble with the clock spring That's the spring that allows those buttons on the steering wheel to work half of yours are out or something along those lines If the buttons on the steering wheel don't work for the air conditioning or the fan or whatever it may not allow the compressor to come on I have not done a tear down that extensively of the air conditioning system to see I did have an '05 car with the clock spring out and buttons were not working on the steering wheel but I did not sink to check the air conditioning system at the time I think it might have been winter I think the heat was working but I didn't put it on to see now I see that I should have run full tests just to see what didn't happen but the air worked in the car prior to the buttons and after the buttons were fixed on the steering I just don't know if the air was working while the clock spring was failing I used the used clock spring too from another car sitting right here.
     
    #7 Tombukt2, Apr 15, 2023
  8. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    At any rate, if the auto and fresh/rec buttons are not both working, that's going to frustrate your attempts to get the A/C trouble codes on the MFD.

    In Gen 2, I think you can also get them with a decent scan tool. A code xy that would show up on the MFD will be a code B14xy on a scan tool.

    I don't know if that's true for all years of Gen 2 though. It was not true in Gen 1.
     
    #8 ChapmanF, Apr 15, 2023
  9. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Thank you all,

    I am trying to get ahold of someone with a good scan tool. As for the clock spring idea, the lower right side steering wheel buttons (Recirc, front and back defrost) don't seem to work, but the upper right hand buttons (phone controls) DO work . . .

    Could this be a fuse or something?

    Also, is there a more advanced scan tool that any of you can recommend?

    Many thanks
     
    #9 JoeVR, Apr 18, 2023
  10. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,855
    3,968
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    No, it is your clockspring.
     
    #10 dolj, Apr 18, 2023
  11. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    #11 ChapmanF, Apr 18, 2023
  12. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Hi everyone,

    Thank you all so much - you are correct - it's my clockspring.

    I got the defrost to turn on and off while turning the steering wheel.

    Would replacing the clock spring help fix my AC problem? Or is that a separate problem?
     
    #12 JoeVR, Apr 21, 2023
  13. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Getting your A/C trouble codes is what would help fix your A/C problem, and replacing the spiral cable might help you get those.

    But you might be able to do it with the spiral cable you've got, if you find a way to turn the wheel so the auto and fresh/recirc buttons will work.
     
    #13 ChapmanF, Apr 21, 2023
  14. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    OK! Wow, I am making some progress, here!

    I figured out that if the steering wheel is turned a full turn to the left, I can use the fresh/recirc buttons.

    I held both and turned on the car -- it flashed two codes -- 21 and 76. I looked online and it appears to be a solar sensor or an ABS sensor -- would these be connected to my AC going out, or is this just a coincidence?

    Thanks!
     
    #14 JoeVR, Apr 22, 2023
  15. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,855
    3,968
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    21 means there was no bright sunlight shining on the light sensor, so unless there was bright sunlight shining on the light sensor, you can just ignore this.

    The A/C inverter stops compressor control and outputs the DTC 1476 (blink code 76) if the rotation load is too great or too small while controlling motor rotation in the A/C inverter. There are two pages of troubleshooting.

    Toyota Service Information and Where To Find It | PriusChat
     
    #15 dolj, Apr 22, 2023
    Last edited: Apr 22, 2023
  16. JoeVR

    JoeVR Junior Member

    Joined:
    Oct 8, 2020
    15
    0
    0
    Location:
    Midwest
    Vehicle:
    2005 Prius
    Model:
    N/A
    Thank you so much for the reply. It sounds like if the rotation load is too great coming from the compressor, that it may likely be the AC compressor that needs replacement.

    But I am eager to troubleshoot this and figure out exactly what the issue is. The link that you included - is there a pdf resource to help me troubleshoot this, or should I purchase a manual?

    Thank you all so much - I think that I am close to getting this properly diagnosed.
     
    #16 JoeVR, Apr 22, 2023
  17. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    You'd be looking for the two pages in the repair manual that make up the troubleshooting section for B1476. There are PDFs floating around the web sometimes of the whole manual or of a particular section you're looking for, and sometimes with the right search one will turn up. It's not always easy to give one link that'll definitely work, because for copyright reasons sometimes the same link doesn't always stay working.

    The ways you know you can always legitimately find them are explained here:

    Toyota Service Information and Where To Find It | PriusChat

    These two troubleshooting pages don't harbor any big surprises. One thing that can definitely make the compressor's rotation load too great or too small is to have the wrong amount of stuff to compress. If it isn't that, then the compressor itself, or the circuit that powers it from inside the inverter, are things to think about.
     
    #17 ChapmanF, Apr 22, 2023
(You must log in or sign up to post here.)