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

A/c Light Flashing

Discussion in 'Generation 1 Prius Discussion' started by thephoenix, May 11, 2011.

  1. thephoenix

    thephoenix New Member

    Joined:
    Nov 26, 2010
    37
    2
    0
    Location:
    West Allis, WI
    Vehicle:
    2001 Prius
    Model:
    I
    Now that I have dealt with my exhaust valve problem, my A/C light flashes which indicates there is something wrong. It does work very nicely for about 15-20 minutes...so I'm hoping nothing mechanical so to speak is wrong...like the compressor or condenser. So wanting to safe money I want to just get my refrigerant topped off, but I would expect that some people would recomned I get a dye test and so forth. Could I get some feedback on this issue. Thank you very much!
     
  2. ea8631

    ea8631 Member

    Joined:
    Oct 16, 2004
    186
    80
    0
    Location:
    Toronto, Ontario
    Vehicle:
    2017 Prius
    Model:
    Technology
    If your A/C work nicely for about 15-20 minute, I think it will be more related to A/C Clutch cannot be engauged. This is because if you have a feron leak you would not get any cold air from your A/C for your first 15 min. My opion is just save the money from recharge your A/C to buy a new A/C clutch. It cost around $250. This is what happen to my 01 prius.
     
  3. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    How did you fix it?

    For the A/C, do you know how to pull the blink codes, e.g. within 5 seconds of turning the car on, press the A/C switch 3 times, and turn the fan from Off to Auto.
     
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,072
    14,976
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    If I remember right, a blinking A/C light before you have even asked for any blink codes has a specific meaning: I seem to remember it means that the compressor rpm has been detected different from what it should be in proportion to engine rpm ... which would have to mean clutch or belt slipping.

    -Chap
     
  5. thephoenix

    thephoenix New Member

    Joined:
    Nov 26, 2010
    37
    2
    0
    Location:
    West Allis, WI
    Vehicle:
    2001 Prius
    Model:
    I
    Thank you so much everyone for your imput...but i belive it was dectecting the rmp differnce....and the reason why i believe is becasue I still had my radiator blocked from the winter time DUH! I removed the pipe insulation from the grill area and no more blinking light: so far but I'm confident I have solved the problem for now
     
  6. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,072
    14,976
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    How strange ... I can't easily see how that would change the engine-to-compressor rpm ratio. Maybe the unsolicited blink can mean more than one problem? If there's a high-pressure limit switch in there (I don't remember), I could definitely see that tripping with the grille blocked. Or maybe the head pressure can really go high enough to make the belt or clutch slip when they don't otherwise?

    Now I'm thinking it would have been interesting to trigger the coded blinks and see what you got, just for curiosity's sake. But it's probably more fun just to have air conditioning. :)

    -Chap
     
  7. prius2001

    prius2001 New Member

    Joined:
    Jan 8, 2010
    7
    1
    0
    Location:
    New York
    Vehicle:
    2001 Prius
    Model:
    N/A
    Wondering if the a/c blinking light problem has been solved, and if the fix re: blocked radiator ultimately worked. I'm having the same issue with my 2001 prius. The A/C blows cold air for about 15-20 minutes, then becomes warm and the A/C light blinks. I've changed the cabin air filter and the magnetic clutch relay (twice), but I'm still having the issue. It also affects the functioning of the defogger, which I suppose relies on the cool air from the A/C when the main defogger is selected. As a trial I drove the car for about 30 minutes and then turned on the A/C for the first time (instead of turning on the A/C soon after starting the car), and instead of blowing cold air for 15-20 minutes, it worked for only about a minute. This makes me wonder if the malfunction has something to do with the car being "warmed up" (e.g., a temperature sensor somewhere?) Any thoughts/ updates?
    Thanks
     
  8. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    The blinking light does indicate a compressor to engine speed rpm mismatch. Rather than the relay, it may be the compressor clutch itself.
     
  9. oldnoah

    oldnoah Member

    Joined:
    Aug 21, 2010
    187
    53
    0
    Location:
    New York
    Vehicle:
    2001 Prius
    Model:
    N/A
    I have had the same symptoms with my AC. How hard is it to replace the clutch? Has anyone here done it?
     
  10. prius2001

    prius2001 New Member

    Joined:
    Jan 8, 2010
    7
    1
    0
    Location:
    New York
    Vehicle:
    2001 Prius
    Model:
    N/A
    Thanks for the reply about the compressor clutch. I wanted to check to see if my weekend experience supports this theory: I drove from NY to Pennsylvania (approx 80 miles) over the weekend and the AC worked the entire way. On the way back it finally started blinking again toward the end of the journey. It was fairly cool this weekend (60's) - does that mean the compressor speed is slower overall (lower RPM) because it doesn't have to work as hard in cooler weather? Is there typically a directional/ proportional relationship at which the rpm mismatch occurs, or does the AC fail whenever a mismatch occurs in either direction (e.g. engine rpm faster or slower than compressor rpm)?
     
  11. lech auto air conditionin

    Joined:
    Sep 5, 2011
    830
    601
    260
    Location:
    san francisco
    Vehicle:
    2012 Prius c
    Model:
    Two
    could be a few things cause the same symptom. after reading this thread and replays, the one with covering the radiator in winter, we dont need that here in San Francisco we think its cold when its 50F in winter.
    #1: If you completely cover the radiator or most of it, with the lack of air flow over the condenser and the heat radiating from the radiator it can drive the high side PSI vary high and cause a clutch to slip and a RPM sensor can see a difference, ( just one of many guess ).
    #2: If a clutch gap get too large from wear, when the A/C first starts the magnetic clutch coil is cold( low resistance of the copper winding = strong magnetic pull on clutch). when the car A/C runs 10 to 20 min the coil get hot from the current running through it ( hot copper windings = weak magnetic pull on clutch ) After the clutch cycles off then when its time to engage again it gets power but it cant pull the clutch. I seen this before.

    #3: You talked about topping of the freon (DON'T ) only fully recover the refrigerant , vacuum the system at least 1 hour if they are just using vacuum gauges and not a micron meter. Then the recharge but weight not using the sight glass!!!.

    #4: You said you changed the relay, that to some time stop working when it gets hot

    its all guess work with out seen the car, go look at some of my photo I have posted only about Prius A/C compressors. Take care of that little A/C system it should last many years, mostly out side force do damage to it.
     
    1 person likes this.
  12. panache

    panache Junior Member

    Joined:
    Jul 2, 2009
    28
    12
    0
    Location:
    Staunton, VA
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I had the same issue (after a year, the A/C would only run for 5 minutes before blinking). Dealer said it was the A/C clutch and quoted a spendy repair, over $1,100. I waited a year (during which the problem got worse and worse) and took it to an independent shop where they quoted me less for the labor. However, they said the clutch "burned" the compressor too because they said everything was running too hot so I had to get a new one too. Found a salvage compressor on ebay for $100, everything works now. Was still not cheap altogether (around $700).
     
  13. Yakuzahi

    Yakuzahi Junior Member

    Joined:
    Oct 2, 2009
    85
    9
    0
    Location:
    Long Island NY
    Vehicle:
    2013 Prius
    Model:
    Three
    I had the same issue last summer and the bottom line is that the clutch was bad, but the compressor was good. No one wants to change the clutch only, so the mechanics create a story to make you change the compressor all together. You can tell that the compressor is good because when the AC was working it was super cold and then 15 min later, when the clutch got hot, it stopped until it cooled down, and then blink again...

    I bought a "rebuilt" compressor from eBay too, but it's not even near rebuilt, it's just a used compressor that got painted. NOT RECOMMENDED AT ALL!

    Who ever has this problem should buy a real rebuilt one for $450.