My climate control was working just fine yesterday, but today I have no air conditioning. When I set the climate control to warm temperatures I get heat, and when it's on cold temperatures I only get outside air blowing in with no air conditioning. When the vents are set to windshield defrost (the button on the far left) it only blows hot air regardless of the temperature setting of the climate control (is this normal? I hadn't noticed this until now.) I checked the Poly V belt and it's fine; it seems that the A/C compressor just doesn't engage. The fan(s) that usually turn on when the A/C is running don't come on at all.

In my car the moment i turn the air blower switch the AC compressor use to engage. The question is this nrmal? But now as mentioned above the AC compressor is not engaging. The freuon gas is ok.

Any ideas as to what may have gone wrong? I've search this forum but was unsuccessful in finding info on this problem. I would appreciate any help I can get before I start poking around under the hood tonight.

I don't recall what runs the climate control in that car, but I'm assuming that you don't have a N-22.

If not, there will be a low-pressure switch somewhere on or near the receiver. That prevents the compressor from starting with insufficient refridgerant. Ensure that you get 12V on both wires of this switch when you think the compressor should be running. Don't confuse it with the temperature switch, if you also have one of those on the receiver. The temperaturse switch should have power whenever the key is on, while the low-pressure switch will have power only when the compressor is demanded.

No voltage at the switch means that the problem either power or something in the cabin. Voltage on one side means the switch is bad or you have insufficient refridgerant, voltage on both sides means that the problem is after this switch, perhaps in the compressor clutch or wiring.

Correct me if i am wrong. Do you mean that switch which is mounted on the top of the AC bottle through which we see the gas flowing once the compressor is working.

If this is the switch you are talking about then it is having two wires on it. So witout starting the engine and with the key in the agnatition switch with the dash lights one, both the wires should have 12 v current in them, or i should start the engine and the should check the voltage in both of the wires on this switch

Thanking you

I was thinking that it was an older system for some reason, but I think you still might have a switch there on yours. The older systems had two switches on that "bottle," one for pressure and one for temperature. Temperature is for the auxiliary fans, pressure is to prevent compressor damage. The temperature sensor had pigtails on it. Does this sound like what's on your car?

I took the car to an AC Mec. He had checked the switch mounted on the AC filter bottle through a tester. It was not getting the current. (On which one can see the gas flow as there is a transparent window). So after that he just pulled a relay as shown in the pic. This relay was behind the battery having around 8 pins or so.(The relay no as shown in the pic is 003-545) While he was pulling the relay I heard the compressor getting engaged for a second. So he just cleaned the legs of the relay and plugged it back to its place.

For the whole day my car AC was working very fine. I asked the tec that what was the defect. He laughed and said even he never knew what was it……………… But thanks God the AC is working till now………

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