A/C condensor clutch doesn't work

[tayninh]

Hi, I have a 2000 Z3 with the 2.5 engine. A/C quit working. Clutch is NOT kicking in. I haven't checked the freon yet, but will do that. I checked the fuses (OK), then swapped the two relays (A/C & Low speed radiator fan) with NO CHANGE. I pulled the "hot wire" off the coil/condensor, and used a "jumper wire" from the under hood "positive terminal" to the condenser power terminal and the clutch DOES kick in and run. I know "low refridgerant" can keep the clutch from "kicking in" but don't have the gauges yet to check that.

MY QUESTION IS: With the car running, temp set to cold, and blower fan set to high, I push the "snowflake button", or on/off button, and it does go in and stay in,,,,,,,,,,,,,BUT, it does NOT light up. Is this an indication that it is a bad switch,,,or just that the bulb has burned out. Should the switch "still be functional" when it is depressed, even when it is "not lit up" or does the bulb work like a fuse, and keep the switch from working when it doesn't lite up? (If you don't ask,,,,you won't find out).

Is the light just an indicator light and has nothing to do with whether the unit is working or not?

Is there a separate "fuse" for the on/off button? If so, where?

Thank you very much and will appreciate any help!
Don

[Randy Forbes]

Bulb.

If you jump around the pressure switch__not literally, but electrically__you can pretty much verify that it's not pulling in the compressor due to (very) low Freon content.

SO then the next question is WHY? Good bet it's just leaking at one of the O-rings/connections, but now's when you need to get someone with real a/c experience and/or equipment involved.

[tayninh]

OK,,,,,,is this "pressure switch" screwed into the back of my compessor? Has a plug with two wires coming into it? Should I just unplug it, then "jumper" the two terminals in the plug on the end of the wire?

[magnetchief]

Stop fluffing about and check the pressures.

Jumping, shorting, disconnecting, guessing, praying and hoping will only cost you time and $$$

Get a friend with a set of gauges.
Or have a shop look at it and make a diagnosis.


Worst case, spend $30 on a can of refrigerant with a pressure gauge.

Don’t ! Buy a can including a sealant.


My AC switch never lit up.
But the AC works fine.

Maybe the lamps are shot

Sent from my iPhone using Tapatalk

[Vinci]

In most situations, if your compressor doesn't kick on when it should, it is because the refrigerant is too low. The compressor has a built-in safety switch that will not allow it to turn on when the pressures are too low, as that would quickly burn it out.

In case you're interested, this is cause the refrigerant in the system carries the compressor oil with it when it circulates, which keeps the compressor lubricated. Insufficient refrigerant in the system means that the compressor won't receive adequate lubrication and will fail.