Page 1 of 3 123 LastLast
Results 1 to 10 of 23

Thread: A/C Not Working

  1. #1
    Join Date
    Jan 1970
    Location
    Brissy! No flannos here!
    Posts
    8,814
    Total Downloaded
    0

    A/C Not Working

    Hi All,
    My A/C has stopped working all of a sudden. And I mean all of a sudden!
    Cold Cold Cold not Cold!

    I searched and read about a few things that cause this but thought I'd seek advice.

    Obviously it could be low gas. I recently had the radiator and intercooler replaced, which necessitated removing the condenser and emptying the system.
    I would have thought that a leak would have the effect of reduced efficiency over time.

    Before I look into the compressor side of it, I was looking for an A/C fuse or relay, but I'm either a dummy or a there isn't one!

    I do have a HSE so it has rear A/C which I believe is a second evap but still only one compressor

    I put my Gap tool on and got the following results:
    System pressure 787.5kPa; Compressor /motor current 212A; Evap temp 37.0 although did reduce marginally over a few minutes; Ext ambient 32.5.

    I'm not sure what to think about the compressor current, that's stupid high, but maybe it's a gap tool thing.

    Thoughts, suggestions?

    Ralph

  2. #2
    Join Date
    Jan 1970
    Location
    Adelaide Hills. South Australia
    Posts
    13,349
    Total Downloaded
    0
    Is possible the Electro Magnetic Clutch has failed therefore while it is spinning, it may not be actually driving the Compressor. Wiring fault or blown fuse or a failed Clutch.

    NB. I am assuming the HSE has such a clutch assembly.

    No idea why you are getting partial operation unless the cause is intermittent.

  3. #3
    Join Date
    Apr 2008
    Location
    Brisbane,some of the time.
    Posts
    13,886
    Total Downloaded
    0
    I don't think the gas is gone at that standing pressure,if its correct.

    Unfortunately,the compresser could be shagged,not pumping,to stop suddenly,or an electrical fault thats stopping the compresser.

    There is an unloader valve that goes in them sometimes,but doesn't sound like yours has those symptoms,and my Indie told me they generally fail in the later 3.0L D4.

  4. #4
    Join Date
    Oct 2012
    Location
    Perth
    Posts
    2,700
    Total Downloaded
    0
    UK cars the under car pipe work corrodes to rear AC and causes fail.

  5. #5
    Join Date
    Mar 2016
    Location
    Perth
    Posts
    4,335
    Total Downloaded
    0
    Quote Originally Posted by Ralph1Malph View Post
    Hi All,
    My A/C has stopped working all of a sudden. And I mean all of a sudden!
    Cold Cold Cold not Cold!

    I searched and read about a few things that cause this but thought I'd seek advice.

    Obviously it could be low gas. I recently had the radiator and intercooler replaced, which necessitated removing the condenser and emptying the system.
    I would have thought that a leak would have the effect of reduced efficiency over time.

    Before I look into the compressor side of it, I was looking for an A/C fuse or relay, but I'm either a dummy or a there isn't one!

    I do have a HSE so it has rear A/C which I believe is a second evap but still only one compressor

    I put my Gap tool on and got the following results:
    System pressure 787.5kPa; Compressor /motor current 212A; Evap temp 37.0 although did reduce marginally over a few minutes; Ext ambient 32.5.

    I'm not sure what to think about the compressor current, that's stupid high, but maybe it's a gap tool thing.

    Thoughts, suggestions?

    Ralph
    There is no clutch. It’s a displacement compressor so a valve varies the output rather than a binary on/off of a clutch.
    2010 TDV6 3.0L Discovery 4 HSE
    2007 Audi RS4 (B7)

  6. #6
    BradC is online now Super Moderator
    No one of consequence
    Supporter
    Join Date
    Mar 2018
    Location
    Perth (near Malaga)
    Posts
    3,544
    Total Downloaded
    0
    Quote Originally Posted by Ralph1Malph View Post
    I'm not sure what to think about the compressor current, that's stupid high, but maybe it's a gap tool thing.
    From what I've been able to ascertain the "compressor current" seems to be a vague interpretation of the displacement valve duty cycle. On mine about ~235 is flat out and it comes back to ~100 at lower loads.

    Your pressure matches your evap temp pretty much on the nose and the pressure is measured high side. Likely the displacement valve is jammed shut or the compressor is toast.

  7. #7
    Join Date
    Jan 1970
    Location
    Adelaide Hills. South Australia
    Posts
    13,349
    Total Downloaded
    0
    Quote Originally Posted by DiscoJeffster View Post
    There is no clutch. It’s a displacement compressor so a valve varies the output rather than a binary on/off of a clutch.

    Thanks DJ, I am not familiar with this noo fangled stuff, but one lives & learns.

  8. #8
    Join Date
    Jan 1970
    Location
    Melbourne, AU
    Posts
    839
    Total Downloaded
    0
    I had poor and intermittent cooling on mine. Re-gas didn't fix, although gas was down a bit.
    Compressor replaced and running cold now. I was surprised at how bad it had become when it came back to normal.
    Happily done under extended warranty.
    _________________________
    1996 D1 V8 - gone
    2002 D2 Td5 ES- gone but still running elsewhere
    2013 D4 SDV6 HSE - gone
    2023 Defender 110SE D300

  9. #9
    Join Date
    Jan 1970
    Location
    Brissy! No flannos here!
    Posts
    8,814
    Total Downloaded
    0
    Quote Originally Posted by BradC View Post
    From what I've been able to ascertain the "compressor current" seems to be a vague interpretation of the displacement valve duty cycle. On mine about ~235 is flat out and it comes back to ~100 at lower loads.

    Your pressure matches your evap temp pretty much on the nose and the pressure is measured high side. Likely the displacement valve is jammed shut or the compressor is toast.
    Thanks! Just as a matter of interest, is it 'easy' to replace a compressor?
    I know it won't be, but I do have one lying around and would be great if I could do it on a weekend!
    I have read that the displacement valve can be replaced as well. I better look into it!

    Ralph

  10. #10
    josh.huber Guest
    Quote Originally Posted by DiscoJeffster View Post
    There is no clutch. It’s a displacement compressor so a valve varies the output rather than a binary on/off of a clutch.
    I'm pretty sure that's incorrect, but I will double check for you. Yes they have a valve to vary displacement or flow, but I'm 99.9% sure there is still a clutch on the front. The high low switch will generally control this and the ECM will control the displacement due to cooling requirements

Page 1 of 3 123 LastLast

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Search AULRO.com ONLY!
Search All the Web!