Ac blowing warm after water pump install.

Discussion in 'Gen 3 Prius Technical Discussion' started by CurtisGreen, Jul 2, 2025 at 6:19 AM.

  1. CurtisGreen

    CurtisGreen Junior Member

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    I replaced the water pump and thermostat. Stupidly, when I took the connector for the AC compressor out, I didn't cover it with plastic. So, when I disconnected the hose from the thermostat housing it filled the ac compressor connector socket with coolant. I blew it out with a can of air and it looked dry. I got everything put back together and went to start the car. The AC was blowing hot and the Check Hybrid system message came on. Would the coolant spilling into that connector socket be enough to kill the compressor? Is there a way to test the compressor to see if it's dead? Could I have caused a leak in the AC lines by knocking into them while removing bolts from the water pump?
     
    #1 CurtisGreen, Jul 2, 2025 at 6:19 AM
  2. CurtisGreen

    CurtisGreen Junior Member

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    This was the pressure. Was the same with car on and AC on and when the car was off.
     

    Attached Files:

    #2 CurtisGreen, Jul 2, 2025 at 6:44 AM
  3. Tombukt2

    Tombukt2 Senior Member

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    That's right no hi and lo sides exist until compressor is on .
     
    #3 Tombukt2, Jul 3, 2025 at 8:36 AM
  4. BiomedO1

    BiomedO1 Senior Member

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    The AC pressure sensor switch is in that general area. Perhaps you knocked it loose or broke a wire????
     
    #4 BiomedO1, Jul 3, 2025 at 8:58 AM
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  5. CurtisGreen

    CurtisGreen Junior Member

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    If i had knocked it loose or broke a wire would it throw a code? I currently have no codes. The car drives fine. I have taken it on short trips to the store. There is refrigerant in the system. I just don't have AC. it blows warm.
     
    #5 CurtisGreen, Jul 3, 2025 at 10:47 AM
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    There could be codes associated with that.

    How about the high voltage (orange) connector to the compressor: any chance it's not in place.
     
    #6 Mendel Leisk, Jul 3, 2025 at 11:54 AM
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  7. Brian1954

    Brian1954 Senior Member

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    If you have the "Check Hybrid System" message, there are trouble code(s) that need to be read with a capable scanner. Reading the trouble codes is the first thing that you need to do.

    If the scanner that you are using can not read any trouble codes, then you need a better scanner. Read post #1 and then scroll down to post #37 in this thread, https://priuschat.com/index.php?posts/3246758
     
    #7 Brian1954, Jul 3, 2025 at 1:19 PM
    Last edited: Jul 3, 2025 at 2:05 PM
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  8. BiomedO1

    BiomedO1 Senior Member

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    Unknown because it's not a critical operational component. Your compressor isn't running, because the high and low side pressure is equal. One of the things the AC system will check before enabling the compressor is freon pressure. No or low freon pressure, no compressor actuation.

    Hope this helps....
     
    #8 BiomedO1, Jul 3, 2025 at 3:01 PM
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  9. ASRDogman

    ASRDogman Senior Member

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    The smart thing to do is to check everything.
    The pressure does equalize, that is normal when it is off.

    You may have shorted out the connector for the compressor. Did you check the fuse?
    You should spray out the wire connector with brake cleaner, and also the connector
    on the compressor. If you have compressed are, blow both connector/connection to clear it out.
     
    #9 ASRDogman, Jul 3, 2025 at 4:20 PM
  10. CurtisGreen

    CurtisGreen Junior Member

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    Oh ok, i have a cheap scanner. I ordered a bluetooth one and will use drprius app to read the codes, Thanks!

    Thanks. I have ordered a scanner that will be able to pick up the hv system codes. i didnt have brake clean on hand but used compressed air and blew the socket out until it was completely dry before connecting the connector back in. I did check the 10 amp fuse in the box under the dash and it was good. I guess at this point im just waiting for the bluetooth obd 2 connector. Is the fact that there is pressure on both sides a sign of there not being a leak that was caused during the water pump replacement or would that still be a possibility?

    I will check the connector but i dont think i would have knocked it loose. I have ordered a bluetooth obd 2 dongle that will let me check hv system codes. Will get back when i see what they are. Thanks for the reply
     
    #10 CurtisGreen, Jul 3, 2025 at 5:02 PM
    Last edited by a moderator: Jul 3, 2025 at 11:39 PM
  11. ChapmanF

    ChapmanF Senior Member

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    There can be a lot of things to check. Generally, though, when there are things the car is telling you to check, it will often be worthwhile to check those things first. That's the point of reading the trouble codes that go with your Check Hybrid System message. The A/C compressor gets its power from the hybrid system and there can definitely be codes related to it.
     
    #11 ChapmanF, Jul 3, 2025 at 5:11 PM
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  12. CurtisGreen

    CurtisGreen Junior Member

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    yes i will scan the codes. w/e the issue is, its related to me changing the water pump. The only thing that didnt go smooth with that was the coolant getting into the connector socket on the compressor and now my a/c doesnt work. hoping i can just swap the compressor and fix the problem. Will find out more when my bluetooth obd 2 dongle comes in
     
    #12 CurtisGreen, Jul 3, 2025 at 6:16 PM
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