element_1one

My a/c won't engage wen i hit the a/c button in the car. the a/c is on but the compressor isn't pumping??? i checked the connections. am i missing something?

LoooseGSR

low on refrigerant? That can be a cause for the compressor to not engage, if there's no pressure.

blah13

I've also heard the comp will shut itself off when the pressure gets too low...and not to jack the thread but its related, if the pressure is low which causes the comp to not engage then how can you recharge it? The comp has to be on and running according to the instructions.

JonGP4

once u put a can of freon on, it will raise the pressure because of the pressure in the can, this should then kick the compressor on.

Vinceg99

The compressor will shut down if the pressure is too high as well. Its just designed to shut down when there is a change in pressure most likely yes its low on feon but if its low there has to be a reason why I would get the system pressure checked.

element_1one

what's the correct pressure?

sleeper4dr

besides low pressure in the system, the problems could be....

1. one of the two ECU grounds (for the relays) may not be working for some reason
*pretty easy to work around if only one ground is dead*

2. the compressor relay is F*cked (old relays die all of the time)
3. the thermostat and/or pressure switch are bad.
*the A/C switch runs thermostat and then the pressure switch in SERIES. you can test the pressure switch connector in the wiring harness for voltage to verify if everything behind it is working*

4. you have a bad/blown fuse
5. compressor clutch is bad
*put a 12volt source to the RED wire that runs to the compressor. if you connect it and it clicks, then the compressor clutch is OK*

6. you have a bad connection somewhere

if you check the pressure and it turns out ok, check the readings at the Compressor relay and pressure switch and see what they are.

hth, Jason

broncoman74

The pressure is low which is keeping the compressor from kicking on. No one sells freon anymore which means if your car has not been retrofitted over to R134a you will have to have it done. If you can do it yourself with the R134a conversion kit that most stores sell you will need to jumpstart the compressor by bypassing the relay and hooking it up directly to 12 volts. In most cases bringing up the pressure in the AC system is not enough to start the compressor. Circulating the R134a into the system will most likely require jumpstarting the compressor or you will end up with the contents in the can not going anywhere and you will be standing there for a long time. Hope this helps!

LoooseGSR

honestly, it's easiest to have it done RIGHT the first time, you'll thank yourself later. Just take it somewhere like Expert Tire or basically anywhere that does A/C. The system will need to be evacuated and pulled to a vacuum of 30 inches of Hg and be able to hold for no less than 15 minutes, preferrably 30. This will ensure no leaks are present. Then basically they'll just recharge your system with R134a. If you don't live in that hot of a climate, and you know there's not much left in the way of freon in your system. Just take out the valves in both the high and low side hoses(they're back near the firewall on the pass. side) and retrofit them with some new couplings from any autoparts store. Make sure they're tight, and then turn on the car, put the a/c on HIGH, and the blower on HIGH as well. Hook up the kit you bought at the store, to the LOW side which is the suction side. after a few seconds the a/c compressor will kick on and you'll have a/c. For the record, CRX's and Civic's that have been switched over from R-12, will need 1.1lbs or 17 ounces of R134a. That is the conversion I did. Good luck.

g2turbo

Here is the problem Im having:


Ok the a/c clutch stopped engaging a few days ago out of the blue.
- I checked both relays and they are good (the ones on the front of the car by the condensor).

-Pulled the plug for the pressure sensor and jumped the harness(this caused the fans to turn on and the idle to raise)

-Checked fuses but can't seem to find one for the AC system

-Lastly I ran a wire to the compressor while the A/C switch was on ect... and the cluch engaged and I had AC for the quick second.

- System has pressure on both high and low sides.

-When the A/C switch on the dash is on the condensor fan is running

Any ideas? I dont really want to hack the car ( cause I could just run a simple relay to engage the clutch ) Id rather fix it correct. Any help?

hugoboss93da

NEED HELP! PLS! My a/c button light wont come on when pressed, no compressor, no clutch nothing. Fan works, temp works, speeds work. But no light on button wich doesent turn anything on. All fuses are good. Is these a special relay for a/c button?

sstupid

The fact that your light on the A/C button doesn't come on could just be the light bulb. My A/C button light used to come on even when nothing in my A/C system worked. I know nobody likes to hear this, but these cars are old. If you want A/C, do like I did and replace EVERYTHING. Works great after that.