A/C Compressor relay

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Lewielewie, Jun 15, 2016.

  1. Lewielewie

    Lewielewie New Member

    Joined:
    Jun 15, 2016
    5
    0
    0
    Location:
    New Mexico
    Vehicle:
    2006 Prius
    Model:
    N/A
    Just less than year ago, dealer replaced all my A/C parts except compressor. Now A/C out again, refrigerant level fine per local mechanic, but no variation from baseline pressures when start A/C, which just blows warm air. Mechanic thinks compressor not working. Before I go to dealer, would like to check relay to compressor isn't bad. Can anyone tell me what it's labeled on diagram under lid of fuse box/relay compartment, or better yet, send picture of that compartment with arrow drawn to the correct relay?

    Thanks, Lew
     
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,070
    6,629
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV


    In your 2006 you would be looking a long time for a compressor relay. :) Your compressor is not driven by a belt and electric clutch, it's driven by its very own, high voltage, three phase electric motor, which is driven at variable speeds by three-phase AC waveforms fed to it from the inverter assembly, under orders from the HVAC computer in the dash.

    There are some pricey parts in that picture, so you probably don't want to pursue the old "replace things until I get lucky" repair strategy. In the new era, to troubleshoot the way God and Toyota intended, you would ask the HVAC computer to tell you what the trouble is, and then fix that.

    In a 2006, starting with the power off, hold down both the 'auto' and 'recirc' steering wheel buttons, while you turn the car on (two POWER presses without touching the brake) ... or READY (one POWER press, while pressing the brake). Wait for a beep and the multifunction display switching to the climate screen. Note down any two-digit numbers shown in the top right corner. These can be looked up in the repair manual.

    I said ON or READY because I don't think it really matters ... I've seen a post that says to use READY, I know just ON works on my Gen 3 (and is what the manual says), I think you get the same codes either way. :)

    -Chap
     
    Qwer and ILuvMyPriusToo like this.
  3. Lewielewie

    Lewielewie New Member

    Joined:
    Jun 15, 2016
    5
    0
    0
    Location:
    New Mexico
    Vehicle:
    2006 Prius
    Model:
    N/A
    Thanks, Chap. Did that procedure, and got "21" code back, although found it in middle between up and down arrows for setting temp on Climate screen, alternating with current temp setting (76). (Upper right of screen just had current outside temp).

    I obviously need a repair manual, but don't have one. Can you tell me which one is best to get, and where to order it? And in meantime, if you are able to find that code in your manual and tell me what it means, or if it's possible to find that out online, I'd be very grateful--although am certainly very grateful to you already!

    All the best,

    Lewis
     
  4. Lewielewie

    Lewielewie New Member

    Joined:
    Jun 15, 2016
    5
    0
    0
    Location:
    New Mexico
    Vehicle:
    2006 Prius
    Model:
    N/A
    Found manual online, but can't seem to find "21" as a diagnostic code. ??
     
  5. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,070
    6,629
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Sorry, didn't see this right away. Pretty sure 21 is the code for solar sensor in the dark. Not a problem if you actually are in dark or shade when you ask for codes. Only indicates a problem if still shown even when sunlight is falling on the sensor.

    But I strongly recommend checking the manual rather than trusting my memory on codes.

    So, if that was the only code shown, then whatever other problems exist will have to be tracked down the hard way.

    -Chap
     
  6. ILuvMyPriusToo

    ILuvMyPriusToo Active Member

    Joined:
    Dec 4, 2014
    676
    443
    0
    Location:
    Outside Philly, PA
    Vehicle:
    2009 Prius
    Model:
    II
    While there isn't a relay, there should be a fuse somewhere that would be worth checking. Surprising the ECU didn't give you a trouble code. Maybe more info would be available over a miniVCI check of that ECU.
     
  7. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,070
    6,629
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The high-voltage system has very few discrete, replaceable fuses, as far as I know ... I'm not aware of any, other than the main one that's co-located with the orange service disconnect at the traction battery.

    -Chap
     
  8. b100

    b100 Member

    Joined:
    Jan 9, 2016
    139
    71
    0
    Location:
    Netherlands
    Vehicle:
    2012 Prius
    Model:
    N/A
    There is a ac fuse inside the inverter.
     
    RD James likes this.
  9. Gregory kitchens

    Gregory kitchens New Member

    Joined:
    May 8, 2018
    3
    1
    0
    Location:
    East Texas
    Vehicle:
    2004 Prius
    Model:
    ----USA----
    I know this is an old thread but on my 04 model my a.c. doesn't work. I get codes
    00, 13, 62 and 74. The copressor doesn' cycle at all, and it reads over pressure on the low side and it does not change when I turn the a.c. on, nor do I see anything in the sight glass. I' assuming the amplifir is out, but it' also throwing 74 so I'm not surem I made a post, but since I just registered (finally) it's still waiting admin approval and has been for a few hours.
     
    Qwer likes this.
  10. Qwer

    Qwer Junior Member

    Joined:
    Mar 21, 2018
    16
    7
    2
    Location:
    Canada
    Vehicle:
    2014 Prius v wagon
    Model:
    Four
  11. Center of Gravity

    Center of Gravity Junior Member

    Joined:
    Mar 18, 2017
    24
    2
    0
    Location:
    New Orleans
    Vehicle:
    2008 Prius
    Model:
    Three
    Same problem here and very perplexed. Did you (Greg or Ower) figure out the issue. It seems to me that Prius Chat is dead, because NO one seems to posting and responding.
    Carl
     
  12. Center of Gravity

    Center of Gravity Junior Member

    Joined:
    Mar 18, 2017
    24
    2
    0
    Location:
    New Orleans
    Vehicle:
    2008 Prius
    Model:
    Three
  13. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,070
    6,629
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    PriusChat isn't really dead, but some posts get more responses than others,

    It's been a year or so since Greg Kitchens posted the trouble codes he was seeing (00, 13, 62 and 74).

    More recently, Qwer posted "I have same problem" but linked to a thread where the code was 23 instead, so it wasn't the same problem.

    Center of Gravity has posted "same problem here" but not said what the codes are yet, so nobody knows if it is or it isn't.

    Threads that get too much like that can end up being sort of skipped over by other PriusChatters who are looking for places they can give useful answers.

    There would probably be more responses to a post that clearly states the symptoms and the trouble codes, and even better if the codes have already been looked up in the manual (more info) and briefly described in the post, to jog the memories of other PriusChatters who might want to help. (As awesome as we all are, we usually don't really have the whole book of trouble codes memorized.)

    Since somebody has to look the codes up anyway, it can save time if one person does that when posting, instead of the multiple people reading the post (who might see the post and think "hmm, interesting, I'll come back to that one some time when the manual's in front of me if I remember to" and then not remember to).
     
  14. RD James

    RD James New Member

    Joined:
    Feb 21, 2019
    9
    0
    0
    Location:
    Hawaii
    Vehicle:
    2006 Prius
    Model:
    II
  15. Jack Myers

    Jack Myers New Member

    Joined:
    Aug 1, 2019
    1
    0
    0
    Location:
    Tulsa, Ok.
    Vehicle:
    2006 Prius
    Model:
    Two
    I just had same problem, 2006 prius. My codes are 21, 23, 43. I do not have a manual but I found the 23 code was a pressure switch, I replaced the pressure switch that is tight next to the high side terminal and it did not fix problem. Any Ideas would be appreciated.
    Thanks
     
  16. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,070
    6,629
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Codes can't be interpreted quite that simplistically. The fortune cookie "pressure switch" might show up next to 23 in some listing of codes, but that doesn't mean the computer is telling you the pressure switch is bad; it has no way of knowing that. It can only be telling you that the signal it's getting from the pressure switch is surprising, which can mean the switch is bad, or the wiring to the switch is bad, or the switch and the wiring are all good and the pressure in the system is surprising. It's up to the human to take the clue from the computer and run it down to the root cause.

    There will usually be several pages of ideas for doing that, in the manual where the code is listed.
     
  17. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,115
    6,120
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Code 23 is DTC B1423 which means there is a problem with the system pressure. Either it is too low (below 28 psi) or too high (above 455 psi.)

    Since you replaced the pressure switch, can I assume that you were able to evacuate the system with a vacuum pump, and recharge the system with R-134a?

    If my assumption is correct, your next step would be to hook up manifold pressure gauges to the low side and high side ports so you can see what the pressure readings are.

    If my assumption is not correct and you did not evacuate / recharge the system, that needs to be done next.

    The high side pressure should be 198-228 psi when ambient air temp is 86-95 degrees F, max fan speed, max cool temp setting, doors open. The low side pressure should be 22 to 36 psi under those conditions. Obviously it is assumed the air conditioner compressor is running.
     
    Raytheeagle likes this.
Loading...