:aigo: just like it says when i turn on the ac ,,,the compressor nor the fans kick in ....it just blows air......robert from 935motorsports hooked up the compressor directly to the battery and the fans kicked in and compressor worked...so the ac was working.....anybody had thisn problem..is there a switch , fuse, relay , or what ever makes the compresor kick in might be bad...or were should i start checking .....any help would be appreciated thank u.....:1zhelp:
ac compressor not turning on
- Thread starter wardog
- Start date
Take it to an a/c shop. There are safety devices that keep it from running when low on refrigerant. You are low on refrigerant, or those switches are defective. They are cut out switches.
does our MKIII's have a pressure switch? when the system gets low on freon it won't kick on the compressor clutch? it might be as easy as filling up the system with more freon. but them you have to ask... where did it leak from. good. luck.
Nick's advice is dead on wardog. The car has a low pressure cutout switch to prevent the compressor from running when the refrigerant is low because the oil in the freon won't circulate and the compressor will burn out. Not saying that's your problem as there are other things that'll keep the compressor off but checking freon is the first place to start. Unless it's been retrofitted your 89 uses R-12, which is the old stuff.
Like JJ said, you do have pressure switches in the system. One is a high/low pressure switch and the other is merely a high pressure switch. The high/low is the one controlling the compressor turning on/off based on the freon and the other high only pressure switch is controlling what your aux fans are doing. The switches are in the engine bay, passenger side, next to the shock tower. Good luck!
I had this exact same problem.... i replaced the two relays that were right under the fusebox and that didn't work.
took it back to the AC place... i don't know how many thermostats or electrodes that tap into the coolant system, but one of them is used for the AC i guess and that one needed to be replaced. also i think there was a relay near the passenger kickpanel that needed to be replaced or something.... i couldn't really understand what the chinese mechanic was saying
but after that was fixed my AC works now.
took it back to the AC place... i don't know how many thermostats or electrodes that tap into the coolant system, but one of them is used for the AC i guess and that one needed to be replaced. also i think there was a relay near the passenger kickpanel that needed to be replaced or something.... i couldn't really understand what the chinese mechanic was saying
but after that was fixed my AC works now.If ALL of the above fails to make it work there is an AC Amplifier up under the dash that can die and stop it working.....
wardog said:
That's $170. Lets see: $20 for a 609 cert, $45 for a manifold gage set and $50-60 for R12 (both from ebay), $10 for an AC book (free if you have a TSRM) and the rest on a cheap vacuum pump and beer (optional). Freedom from dependence on others? Priceless
There is a simple fact about A/C systems. The freon molecules are smaller than Oxygen.
The freon WILL leak out. That is why they switched to R134a.
The best thing you can do to help your system, and save you $$$, is to RUN it year round, for at least 10 minutes every 3-4 days minimum. This will keep the oil spead evenly throughout the system, and keep the seals coated (freon won't leak -as much- from an oil coated seal or gasket).
Running it also keeps the oil from settling in the compressor, bottom of the evaporator, condensor, and receiver/dryer. The most wear on a compressor is when you first turn it on after a long period of OFF (like winter).
The Automatic Heater/ac systems are very complicated. Many things can go wrong. Usually its just low freon.
There are coupons specials for a/c service (ours is $29.99 plus freon). Repairs are extra. R12 is $65 lb. R134a is $26. Converting over to R134a is $210, total. Converting should be done by a professional, because if done wrong, it WILL kill your compressor.
Changing out a dead compressor for a new (top of the line) aftermarket one, with rec/dryer, cost about $900.:icon_evil
Tip...too much oil in the system will not let it get as cold, and more can kill the compressor.
Too much freon will give same results.:evil2:
The freon WILL leak out. That is why they switched to R134a.
The best thing you can do to help your system, and save you $$$, is to RUN it year round, for at least 10 minutes every 3-4 days minimum. This will keep the oil spead evenly throughout the system, and keep the seals coated (freon won't leak -as much- from an oil coated seal or gasket).
Running it also keeps the oil from settling in the compressor, bottom of the evaporator, condensor, and receiver/dryer. The most wear on a compressor is when you first turn it on after a long period of OFF (like winter).
The Automatic Heater/ac systems are very complicated. Many things can go wrong. Usually its just low freon.
There are coupons specials for a/c service (ours is $29.99 plus freon). Repairs are extra. R12 is $65 lb. R134a is $26. Converting over to R134a is $210, total. Converting should be done by a professional, because if done wrong, it WILL kill your compressor.
Changing out a dead compressor for a new (top of the line) aftermarket one, with rec/dryer, cost about $900.:icon_evil
Tip...too much oil in the system will not let it get as cold, and more can kill the compressor.
Too much freon will give same results.:evil2:
Listen to this guy, he knows his A/C. He's in the Mojave for crying out loud
Yep, truer words were never spoken. Running year round keeps the shaft seal lubed, all kinds of good things. As for converting I keep badmouthing them but you can bet the death kits will continue flying off the shelfs. Bad for the owner but good for guys who do repair. What the heck is up with Suva anyway? Used to be cheap.
Yep, truer words were never spoken. Running year round keeps the shaft seal lubed, all kinds of good things. As for converting I keep badmouthing them but you can bet the death kits will continue flying off the shelfs. Bad for the owner but good for guys who do repair. What the heck is up with Suva anyway? Used to be cheap.
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