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Code 21 after replacing compressor n evac/recharge ac

Discussion in 'Generation 1 Prius Discussion' started by Jeff Girard, Jun 29, 2019.

  1. Jeff Girard

    Jeff Girard Junior Member

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    2001 Prius Gen 1 I replace the AC compressor which was locked up and took it to a shop and had the air conditioner evacuated and recharged he then they told me that the AC wasn't working after one minute it would throw code 21 I disconnected the trunk battery and still could not clear the code and get it to blow cold I clean the solar sensor wiped it off and I'm at my wit's end with this I think it's a simple clearing the code because I find it to be coincidental that the compressor and the solar sensor went at the exact same time unless driving a car for the winter with no AC could have caused the problem but I believe the AC code has been there for months until I replace the compressor any help any direction any ideas would be much appreciated thank you
     
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  2. dolj

    dolj Senior Member

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    A/C code 21 is simply is telling you that the solar sensor does not detect bright sunlight. As long as your car was not in bright sunlight when the code came up, then there is no problem. If you are seeing the code in bright sunlight (or simulated with a bright light source directed into the solar sensor), then you do have an error with solar sensor (or related plugs, cables, etc) and that does warrant further investigation.

    Hope that helps.
     
    #2 dolj, Jul 2, 2019
    Last edited: Jul 2, 2019
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  3. Dxta

    Dxta Senior Member

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    +1. Did you vacuum the entire system using a vacuum pump, etc? Was the compressor oil(ND11) used during the installations?
    Try checking the fuses, etc
     
  4. dolj

    dolj Senior Member

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    I believe Gen 1 uses ND-8, Gen 2 on uses ND-11.
     
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  5. Sandy Meyers

    Sandy Meyers Member

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    Could someone briefly please explain why a nonfunctional solar sensor affects the AC. What difference does it make? Couldn’t I typically run the AC at night if I wanted to to chill the car down if the ambient temperature was 95*. For some reason I’m just not understanding why the solar sensor is important for AC. I’m currently having an AC problem with my Gen 1 so this would help me in the broader picture. I’m getting no solar codes on a reader at the moment.
     
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  6. ChapmanF

    ChapmanF Senior Member

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    It doesn't affect the A/C very much; it's just a comfort feature. If you're driving down a shady tree-lined avenue, or out of a parking garage, and into the blazing sun, it will crank the blower speed up a couple notches for you, ideally before you even notice you want it, and back down a notch or two if you drive into shade again. So the solar sensor could be totally b0rked, and all it would mean is that sort of subtle auto-adjustment wouldn't happen.

    The only reason there even is a code 21 is to give you a way of checking whether the sensor does work or not, since its effect is otherwise so minor you wouldn't have much way to tell. So, the car just always shows a code 21 whenever strong light isn't shining on the sensor. Strong light, no 21. Shade or diffuse light (or no light), 21. That's just how you confirm the sensor works.
     
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  7. lech auto air conditionin

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    Let me see if I understand your wording correctly.
    1: The compressor would run for one minute? and cool and then shut off?.
    2: or when you engage the AC nothing happens at all no noise no click absolutely nothing .
    3: you can ignore the solar sensor like explained above every time you’re in the shade there’s always a code 21 until you move it out in the bright sun.
    4: as for the type of oil in a GEN one as explained above GEN one uses ND-8 which is a double end capped PAG oil. Which mean unlike the universal or other PAG oil’s sold on the market. It’s a molecule chain to put it in layman‘s terms is locked up or satisfied at both ends of the molecule as to not link to or bond on to moisture as easily. It also has a higher degree of anti-corrosive additive package added to the oil far superior to other manufactures PAG oil.
    5: you stated the compressor was locked up. Usually but not 100% of the time when you have a locked up compressor it started slowly degrading breaking apart shedding metal shavings that follow the refrigerant flow into the condenser and start plugging up the condenser. If this was the scenario somebody unknowingly would just throw on another compressor fill the system refrigerant and if it was plugged up enough you can get an instant high side pressure of upwards of 440 psi and a high-pressure safety switch could kick in and shut off power to the clutch. On all these new style condensers when you have a locked up compressor you always flip them over to clean them out inspect their old oil see how dirty it is if not oil comes out fill them up with some lacquer thinner brake cleaner carburetor cleaner shake them around and pour out and see if tiny metal flakes come out if so you replace the condenser you flush out the lines and it’s very highly recommended to replace that expansion valve sometimes you could get away with not replacing the expansion valve but legitimately I would give you no warranty and neither with the manufacture if you skip that procedure.
    6: May need a little bit more information here but with what was provided that’s about all I can say.
    7: did you notice when the compressor does not start do you get orange blinking light on your AC button can’t remember off the top of my head if this one does that.
    8: Do you notice when you press the AC button do you hear the click of the clutch while you have it on full fan in the Max AC position th do you notice when you press the AC button do you hear the click of the clutch while you have it on full fan in the max AC position. The max AC position on the GEN one Prius is important to keep the engine running.
    9: you did not state if this was a new compressor that was installed or a used compressor that was installed. May make a difference on the diagnostic route depending whether or not the compressor ever engaged when hitting the AC button. a: if AC compressor never engaged and it is a used compressor check the clutch gap if it’s over 16 to 20 some thousands of an inch adjust can gap closer look up specifications don’t remember it off the top of my head but around 16,000 th or less a little bit. It’s something I do by eyesight and feel I don’t even know longer have to look up specifications or use measurement devices. B: Locate compressor AC magnetic clutch relay. When the AC button on the dash is pushed does the relay click sound or buy touch feel. If it does swap out the relay for adjacent similar relay just for a quick test. c: this recommendation should only be performed by somebody who is familiar with jumping relays as to not to cause damage so ignore this recommendation if you are not fully aware of what to do unfortunately there are many mechanics and shops who do not under stand electricity very well and they consider relays mysterious magical little black boxes so if you have a technician do this there’s ones who know it like the back of their hands and then there’s those who don’t. Jumper the high current side power delivering two prongs of the relay this will permanently in gauge power if available if the fuses good directly to the wiring to the magnetic field coil engaging the compressor permanently as long as you have the jumper in place. If you have power at this location and you jumper it and the magnetic clutch still does not come on no click sound no spinning of the clutch. 1: Bad wiring from that point to the clutch. 2: Use compressor magnetic field coil bad. 3: clutch gap way too big. 4: can’t remember if this one has a thermal overload protection mounted in the side of the case of the compressor where the wiring will drop out into the thermal overload it could be open or closed and then allows current to pass through to the magnetic field coil.
    Quick thoughts off the top of my head still could be more with what limited information received.
    Another thought older AC machines just within the last decade their accuracy at wait to fill refrigerant is plus or minus roughly 3 ounces which is extremely large amount on a tiny Prius system I tell people to stay away from automated air condition machines that are more than five years old especially if they’re 10 years old or more.
    Worst case scenario someone tried to use the little cans I won’t even go trying to explain the problems caused down that rabbit hole. A large portion of our burned up compressors come from those guys with the cans, must remember to send them a Christmas card with A commission check for making us so much business burning out Prius compressors.
     
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  8. Jeff Girard

    Jeff Girard Junior Member

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    I am new to the Prius chat and believe it or not just read your reply and hopefully you will get my reply I want to thank you for your time and information fast forward to now May 14th 2020 thecthe that was put in was a brand new compressor that I bought It came with the oil expansion valve and I believe it's the condenser filter it's about 10 inches long and about two fingers wide and white feels like there's charcoal in it I've been digging and digging trying to figure out what the hell is wrong with my AC I learned that the solar sensor code means nothing but and here's what happens like turn the AC on and it kicks in and starts to blow cold and after 3 seconds shuts off and starts blinking I can turn it off turn it back on and it'll do the same thing well I live in Florida and it's starting to get hot and it's the wife's car and I'm really trying to fix this now I took it to a Toyota specialist not a dealer he hooked up the gauges and said I got super high pressure he said I have a bad compressor I he thought I got a used one or rebuilt and I told him no it was brand new he said well what I would do is take the freon out try to recharge it and see what happens well I had my friend last night removed the freon and with no freon on the system ran and the light didn't flash now of course it didn't get cold but what that kind of tells me is I guess the pressure switches work so I got a can of the freon with the gauge today and put two little pumps of it and that's all it took to get me high pressure and I try to turn the AC on I couldn't get anything I got a code 23 nowand it's not letting me put a lot of freon in it now I did not replace the expansion valve nor did I put the condenser filter in from how it looks You got to I guess take the condenser out because there doesn't look like a way to get it up underneath there where it sits on the frame It doesn't look like they made a access hole so that's where I'm at and any help anyhow anyway would be greatly appreciated I'm just at a loss I mean you know I don't know... the Prius specialist that I spoke to call I called him last night and talked to him for a while and you know he gave me them few ideas to try so maybe my condensers plugged or maybe I got to replace that filter I don't know I still have the old compressor so I will try to dump the oil out to see if there's anything metal or anything in there but we opened up the line where the low pressure where you put the freon in we open that line up and you know just wipe the finger in there just to see if it was dirty or if there's any crap in there and it was clean so it closed that up and like I said ran ran it and it did not throw a code like the AC light stayed on and you know it seemed like it was functioning it didn't go into a blinking mode and I guess I'm repeating myself because I'm using talk to text but try to put a little bit freon instantly you know I only put a tiny bit and the gauge was reading high I release the pressure on the high side to relieve the pressure and try to almost burp the system see what I can come up with so that's where I'm at a code 23 and I will try anything I read what you said about jumping relays I completely understand that I went to school for electronics or relays just to switch on off on off and I believe in that car if I'm not staking through digging through information that you can switch like the horn relay with the AC relay to test them I'm not sure if that go if I've read it on a gen one or not because I've been reading and watching YouTube videos and I mean for months I've been digging at this so again I appreciate any help thank you and have a great day
     
    #8 Jeff Girard, May 14, 2020
    Last edited by a moderator: May 14, 2020
  9. Jeff Girard

    Jeff Girard Junior Member

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    Believe it or not it's May 2020 I do not have this problem resolved to explain it a little better I did post lower down in this thread a whole explanation that may be you can weigh in on but I had a new compressor that I bought that came with the oil came with o-rings came with expansion valve and a sock with like charcoal in it about two fingers wide 10 in long I believe it goes in the condenser but it seems like you can't just access it from underneath I see the Allen spot But I don't see an access hole but I did not take the splash guard down last night I went to a pre-especialist he put my car on his gauges and said you got high pressure it's way too high your compressor is probably bad I told him it was a new compressor and he said he can't find a new compressor for it I said well this was last summer and it was definitely new so he told me get the freon out put new freon in kind of burp the system and you know see what you get well I did that you can hardly tell there's any freon taken out of the can yet that gauge on the can or was way high now when we evac the freon last night and turn the AC on the light did not blink my original problem was after we put the compressor in I took it right to a place and they evacked and recharged my system and said it came up with a solar sensor code so they weren't pretty as special as they didn't know about it and believe it or not I just found this thread and your replies today I figured out how to get into my account and found my post so when I tried putting freon in just a little bit it was very high pressure and I it goes to you know it runs but then the car shuts off the lights stay on so I did the turn the key and press the AC to get the code and I got a 23 and that's where I'm at so if there's any suggestions you have please let me grateful so the wife doesn't sweat and we know how happy wife happy life goes and a sweaty wife is not a happy wife we live in Florida 54 years old and I got to get this fixed it's driving me crazy and I know this has been since July and I spent I probably spent well over a hundred plus hours digging at this problem and trying to figure it out being on a fixed income it's you know I got to try to save what I can save on this and you know I don't know we did not put the expansion valve in because I believe that was like a very long and hard process because it's up in the dash and you got to take the dash apart and all that crap so that wasn't done anything you can help me with would be great I did make a comment in this thread that got a little lengthy so if you want to read that and hopefully you find this and read this and can help thank you and I hope you have a great day
     
  10. Jeff Girard

    Jeff Girard Junior Member

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    Yes it was