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2002 Prius A/C Light Flashing

Discussion in 'Generation 1 Prius Discussion' started by Yakuzahi, Jun 30, 2010.

  1. Yakuzahi

    Yakuzahi Junior Member

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    Hi
    I'm not so sure what is the problem because when the ac light flashing
    and I'm closing the ac switch and turn it back on the ac start to cool again but start flashing after few min.
    Any idea?
     
    #1 Yakuzahi, Jun 30, 2010
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Re: 2002 Pirus A/C Light Flashing

    Check your owner's manual but it sounds like you may need AC service. This is one of those times when I would just take the car to a Toyota Service center and let them pull the codes and make a diagnosis.

    I tend to be skeptical of do-it-yourself AC maintenance because of the leak risk. The refrigerant is probably less bad than what had been used before but still, it is like my 'slow leak' tire. I can air it up when it shows low but the right thing is to repair or replace it.

    Bob Wilson
     
    #2 bwilson4web, Jun 30, 2010
  3. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Thank you Wilson.
    I just thought to grab sub sero from auto zone
    and see if it will help.
    What do you think?
     
    #3 Yakuzahi, Jun 30, 2010
  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Re: 2002 Pirus A/C Light Flashing

    What an AC shop will do is look for leaks. Although you can replace lost refrigerant, there is a certain amount of lubricant needed for the compressor (at least in most car systems.) It might work but I think you're risking the compressor ($$$).

    You may have to join the YahooGroup but here is one report that leads to my skepticism:
    Yahoo! Groups

    Here is a similar thread:
    Yahoo! Groups

    If you decide to perform the experiment, please take photos and post your results. We often learn from the experience of others.

    While you are in there, you might want to check the health and status of your belt. It isn't very big and they seem to last a long time . . . still it is best to patch the roof before the rain storm.

    Bob Wilson
     
    #4 bwilson4web, Jun 30, 2010
  5. vincent1449p

    vincent1449p Active Member

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    Re: 2002 Pirus A/C Light Flashing

    Hi Yakuzahi,

    According to the Repair Manual (RM957U), there are 2 possibilities; Compressor lock sensor circuit or A/C amplifier.

    You may want to perform the following checks to get the DTC from the blinking A/C light:

    1. Within 5 secs. after turning the ignition on, press the A/C switch 3 times and turn the blower switch from OFF to AUTO.
    2. Check that all the indicators light up and go off at 1 sec. intervals of 4 times in succession.
    3. After this, the DTC check mode will start and you can read the DTC from the number of blinks of the A/C indicator.

    If there are no malfunction, the indicator will blink at 0.5 sec. ON, 0.5 sec. OFF and repeats. If there are malfunctions detected, the number of blinks will be the DTC and repeats until you cancel the check mode by switching the blower switch from AUTO to the other positions.
     
    #5 vincent1449p, Jun 30, 2010
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  6. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Hi
    Thanks for the info but i can't see the ac switch blinking at all after all the process.
    any idea why?
    Thanks
    Zach
     
    #6 Yakuzahi, Jul 1, 2010
  7. Brettinmaine

    Brettinmaine New Member

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    Re: 2002 Pirus A/C Light Flashing

    I had the ac light flashing on one of my cars a couple months ago. A new cabin air filter fixed the problem. Has worked fine even in very hot weather. Do this first if you haven't.
     
    #7 Brettinmaine, Jul 2, 2010
  8. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Thanx i will give it a try.
    the cabin air filter locate behind the glove box?
     
    #8 Yakuzahi, Jul 4, 2010
  9. Brettinmaine

    Brettinmaine New Member

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    Re: 2002 Pirus A/C Light Flashing

    Yes that's it.

    They get dirty and clogged faster than you might expect.
     
    #9 Brettinmaine, Jul 5, 2010
  10. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Well i did change it but still i have the same problem.
    I even changed the magnetic relay (cost me 78$) and it didnt help :(
     
    #10 Yakuzahi, Jul 7, 2010
  11. statultra

    statultra uber-Senior Member

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    ok one way we can figure out whats going on is, as soon as you put on the a/c the light blinks?

    you dont hear the magnetic clutch "click" to engage the compressor?

    if it does click on i would take a look at the sight glass which is near the inverter, it should be clear
     
    #11 statultra, Jul 8, 2010
  12. Yakuzahi

    Yakuzahi Junior Member

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    Hi
    Well it doesn't start blinking right away; the A/C is cooling when I start my car in the morning for 20 min, and then begins to blink. When I'm in park, I can hear the clutch click when the light is on and stop when it is blinking.
    Tomorrow, I'm going to take my Prius to the shop of a friend of mine and see if he can help. He said on the phone that he thinks the problem being caused by the cooling belt.
    The only information that I find on many websites is that this is a problem with many Toyota cars.
     
    #12 Yakuzahi, Jul 8, 2010
  13. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Finally i got the test to work!!!
    I got the code 21 but i will wait for tomorrow morning for the car to be in direct sunlight and check again when the A/C light is blinking.
     
    #13 Yakuzahi, Jul 10, 2010
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  14. muleears1

    muleears1 New Member

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    Re: 2002 Pirus A/C Light Flashing

    Mine just started displaying the "21" code too. My research found that points to the solar sensor. Could it be anything else?
     
    #14 muleears1, Jul 11, 2010
  15. Yakuzahi

    Yakuzahi Junior Member

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    Re: 2002 Pirus A/C Light Flashing

    Make sure you doing the test in direct sun light, during a hot day.
    when you check for codes at night time you will get Code 21 like me.
    When i did the test today, the light was blinking fast meaning that there is no fault at all.
    I think you need to wait for the A/C to blink and then preform the test.
    More about code 21:

    Code 21 is open or shot in solar sensor circuit. Possible trouble area are:
    1. solar sensor
    2. Harness or connector between room temperature sensor (locate underneath the shift lever, behind the small vent) and a/c amplifier, or
    3. A/C amplifier.
     
    #15 Yakuzahi, Jul 11, 2010
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