1990 c4 a/c won't turn on
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From: edison nj
1990 c4 a/c won't turn on
this is for people that have a/c knowledge
ok here's the deal i work on all my stuff but this car has a lot of tricks. last year i put a new low side a/c line and high side line flushed system re-did with 134.a worked great. just this past week nj got a heat wave now a/c won't kick on. checked low side nipple with a nail has gas in line next step checked gas amount with gauge was NOT low! thinking that's why a/c clutch would not kick on. started to fill ALITTLE GAS TO SEE WHAT HAPPENED clutch kicked on for a few seconds than stopped. a/c system is full so so i went to low side switch and jumped it with a wire to get a/c clutch to kick on will not kick on manual check a/c clutch spins freely not siezed at all never made noise . checked fuses ok. how many relays and switches any one know? also can the dash cluster for a/c and heat be bad? noticed that when i turn temp down green light blinks on and off .
ok here's the deal i work on all my stuff but this car has a lot of tricks. last year i put a new low side a/c line and high side line flushed system re-did with 134.a worked great. just this past week nj got a heat wave now a/c won't kick on. checked low side nipple with a nail has gas in line next step checked gas amount with gauge was NOT low! thinking that's why a/c clutch would not kick on. started to fill ALITTLE GAS TO SEE WHAT HAPPENED clutch kicked on for a few seconds than stopped. a/c system is full so so i went to low side switch and jumped it with a wire to get a/c clutch to kick on will not kick on manual check a/c clutch spins freely not siezed at all never made noise . checked fuses ok. how many relays and switches any one know? also can the dash cluster for a/c and heat be bad? noticed that when i turn temp down green light blinks on and off .
Last edited by mike pinto; Jun 10, 2008 at 08:52 PM. Reason: SPELLING
Le Mans Master
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From: San Diego, Ca
The flashing LED is indicative of a troublecode and if set, nothing works. Go here to see how you retrieve them: https://www.corvetteforum.com/techti...=193&TopicID=2
Clear codes by removing power from the Programmer or simply disconnecting and reconnecting the battery.
Clear codes by removing power from the Programmer or simply disconnecting and reconnecting the battery.
Thread Starter
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From: edison nj
ac codes
got 00-09 1-64 2-70 3-61 4-122 5-106 6-28 7-00 9-00 10-00 11-00 12-155 16-107 17-127 19-81 20-69 21-150 22-175 23-128 24-128 30-43 31-171 34-153 35-00 36-00 37-07 theses are the codes i got when done one by one does any one no where the relay switch is for ac clutch motor
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From: edison nj
my vet
i have been trying to sell this car for 2 years now shes hounted whe wont let me sale her its driving me nuts and broke last year. i spent the hole driving season just getting it running would not start fainly it was a BAD fuel INJ here comes this season driving it rear wheel hub than the rear brakes where bad did the work . ready to sell now the ac clutch will not turn on what the hell am getting neck surgery soon i just want to sell this car before she makes me poor i got this car from a freind to make a fast turn around well that shore didn't happen its been 3 years now .IF ANY ONE HAS ANY INSIGHT ABOUT AC ON THIS CAR PLEASE HELP I DONT HAVE THE MONEY FOR A SHOP .
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
i have been trying to sell this car for 2 years now shes hounted whe wont let me sale her its driving me nuts and broke last year. i spent the hole driving season just getting it running would not start fainly it was a BAD fuel INJ here comes this season driving it rear wheel hub than the rear brakes where bad did the work . ready to sell now the ac clutch will not turn on what the hell am getting neck surgery soon i just want to sell this car before she makes me poor i got this car from a freind to make a fast turn around well that shore didn't happen its been 3 years now .IF ANY ONE HAS ANY INSIGHT ABOUT AC ON THIS CAR PLEASE HELP I DONT HAVE THE MONEY FOR A SHOP .
I would take it to a shop that deals with R12. Better to spend $100 on a determination than guess on expensive parts.
You will need 30 something ounces of R12, that's $100 right there.
My guess is that the R12 leaked out and needs to be recharged.
OR you have a high or low pressure switch problem.
I'm not an expert on AC.
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From: edison nj
Ac
CARS NUTS ya know about rock auto whats good about tham are the pics. well checked relay was ok checked fuses ok . toke pos battery wire off for a min put back on . strarted car ac clutch went back on now i have ac again what can be doing that with ac clutch thats a new one for me .does any one have a clue why the car did this and will the ac clutch stop again . like i said i jumped the ac low line plug clutch would not come on manuely. parts are not bad price what got me whas fuel inj 1 bad shorted out fuel rall on car called muilty tec inj where knowen to short out . but back to ac any one who may know why the car did this
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From: edison nj
buy the way
thats why i said only respond if you have ac info you can retro fit older cars with 134-a and they will work fine done this with 20 cars if you know any thing about r12 its alot more here in nj people realy dont deal with it what i was told you can yous this stuff called hot shot r14 can be used with r12 134-a cast around 10.00 a can
Le Mans Master
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From: San Diego, Ca
09 means it's out of gas - disconnect and reconnect the battery and see if it resets. Once that code sets, the ECM won't ground the compressor relay until it's cleared. That prevents damage to the compressor (as if it ran empty or low, there wouldn't be enough refrigerant to carry the oil charge). If it resets, it has another leak - look on the hood above the compressor for oil which would be indicative of a shaft seal leak. I wouldn't just dump more gas in it either - take it to Pep Boys or an a/c shop to find out where the leak is and then fix it or if you want to get rid of the car, sell it as is. It's 18 years old, I have no idea how many miles it has on it, but things tend to break at this age.
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From: edison nj
did you read my ad
Here's the bad news, everything on that car is expensive either way you go. Stick with R12, expensive, convert to 134, that's expensive too. Rock Auto has all the parts but many aren't cheap.
I would take it to a shop that deals with R12. Better to spend $100 on a determination than guess on expensive parts.
You will need 30 something ounces of R12, that's $100 right there.
My guess is that the R12 leaked out and needs to be recharged.
OR you have a high or low pressure switch problem.
I'm not an expert on AC.
I would take it to a shop that deals with R12. Better to spend $100 on a determination than guess on expensive parts.
You will need 30 something ounces of R12, that's $100 right there.
My guess is that the R12 leaked out and needs to be recharged.
OR you have a high or low pressure switch problem.
I'm not an expert on AC.
i stated that system was fully charged. please read before you put your 2 cents in thats whats wrong with people in one ear out the othere i love when people like to hear them selves talk. read ad read ad why is there a tech form than if people like you dont know any thing about a car dont answer ad
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
i stated that system was fully charged. please read before you put your 2 cents in thats whats wrong with people in one ear out the othere i love when people like to hear them selves talk. read ad read ad why is there a tech form than if people like you dont know any thing about a car dont answer ad
Thread Starter
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From: edison nj
are there any real tech people on this sight
is that how people get to be a CF Senior Member just answer with any thing this sight should only have people that are gear heads and fix cars for a hobby to help peolpe out .not just responding with junk i can tell i will move on with this sight to be a senior u most answer a ad with help and if that person gets his car fixed thats howyou get to a higher level. not buy responding to any ad to get higher up thats my 2 cents
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From: Savannah Georgia
I had a similar problem with the a/c clutch on my 90 not engaging sometimes, was just a bad relay. if you take of the hush panel on the drivers side, you should find 2 relays roughly above the gas pedal, 1 of them is the starter enable relay the other is for the a/c. You should be able to pull it and have it tested, the relay was about a $12 piece
Le Mans Master
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From: San Diego, Ca
Gee - I thought I was helping. Whether or not it's full of gas doesn't matter. The ECM thinks that it's empty and it isn't going to ground the Relay. Here's how it works: the low pressure switch is in line with the Relay which is driven by the ECM. The ECM monitors how often those contacts open and close and when they start to do so rapidly - which is what the low pressure switch contacts do when it starts to run out of gas - it removes power from the Relay and the low gas trouble code (9) is set. If you recharged an empty system, and you said you rebuilt it, you should have had to clear this code before it ran again. If you didn't, well it's finally started to work the way it's suppose to. Clear it - disconnect and reconnect the battery - and see what happens. Why tear into anything before you try something simple? And if the code resets, good indication that enough has leaked out to make it work the way it's suppose to. I can't help that, but if you were close, I could fix it.
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From: edison nj
I had a similar problem with the a/c clutch on my 90 not engaging sometimes, was just a bad relay. if you take of the hush panel on the drivers side, you should find 2 relays roughly above the gas pedal, 1 of them is the starter enable relay the other is for the a/c. You should be able to pull it and have it tested, the relay was about a $12 piece
Thread Starter
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From: edison nj
Gee - I thought I was helping. Whether or not it's full of gas doesn't matter. The ECM thinks that it's empty and it isn't going to ground the Relay. Here's how it works: the low pressure switch is in line with the Relay which is driven by the ECM. The ECM monitors how often those contacts open and close and when they start to do so rapidly - which is what the low pressure switch contacts do when it starts to run out of gas - it removes power from the Relay and the low gas trouble code (9) is set. If you recharged an empty system, and you said you rebuilt it, you should have had to clear this code before it ran again. If you didn't, well it's finally started to work the way it's suppose to. Clear it - disconnect and reconnect the battery - and see what happens. Why tear into anything before you try something simple? And if the code resets, good indication that enough has leaked out to make it work the way it's suppose to. I can't help that, but if you were close, I could fix it.
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From: edison nj
ac i think is working right now but my head lights
like i said this car is driving me nuts now the head lights come on but turn only 1/2 way up .
i got to run out and flip them up fast or they will stay 1/2 up doing on both sides.
i got to run out and flip them up fast or they will stay 1/2 up doing on both sides.
Last edited by mike pinto; Jun 11, 2008 at 10:47 AM. Reason: face
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From: edison nj
thank you
I had a similar problem with the a/c clutch on my 90 not engaging sometimes, was just a bad relay. if you take of the hush panel on the drivers side, you should find 2 relays roughly above the gas pedal, 1 of them is the starter enable relay the other is for the a/c. You should be able to pull it and have it tested, the relay was about a $12 piece
Thread Starter
Intermediate
Joined: Sep 2006
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From: edison nj
thank you
09 means it's out of gas - disconnect and reconnect the battery and see if it resets. Once that code sets, the ECM won't ground the compressor relay until it's cleared. That prevents damage to the compressor (as if it ran empty or low, there wouldn't be enough refrigerant to carry the oil charge). If it resets, it has another leak - look on the hood above the compressor for oil which would be indicative of a shaft seal leak. I wouldn't just dump more gas in it either - take it to Pep Boys or an a/c shop to find out where the leak is and then fix it or if you want to get rid of the car, sell it as is. It's 18 years old, I have no idea how many miles it has on it, but things tend to break at this age.
