A/C not working, need help ASAP!

M3GA · 06-09-2008, 03:33 PM

Hey Guys,

My A/C is not working, and it's damn hot!

The freon was empty, so had it filled. Mechanic checked the compressor and it is grounded, so working condition. The fuses were not blown. He said it might be the digital climate control module?

We disconnected the battery, and when connected again the compressor worked for a minute and then shut off. The compressor turns on and off sporadically (mostly off

).

What could be the issue? If it is the cc module where can I get one cheap?
Could it be a resistor on the cc module board (probably an easy fix)?

Everything else seems to be in working condition.

2003 BMW 330Ci Coupe

Thanks.

noid · 06-09-2008, 10:02 PM

Over filled. When the compressor is over filled it will turn on and off on and off

Mikey83 · 06-09-2008, 11:12 PM

You know the pressures it was running at? also theres a bunch of safeties aka. high pressure, freeze stat etc.

Would look into that.

M3GA · 06-11-2008, 09:01 AM

Thanks for all the replies. The mechanic tested to see if the system held at (I think) 30psi. When the system held the pressure, it was assumed no leaks. We filled the system with R134a. The previous owner had a supercharger installed in the car, and we thought they may have emptied the ac and never re-filled it, for whatever reason???

A couple of months ago my coolant level was low, so I topped it up with straight coolant, not a 50-50 mix. Can this be a reason why the ac compressor is not turning on? Something to do with temp?

Basically, I'm looking for reasons why the compressor wont turn on and stay on. Right now I dont turn the ac switch on at all, windows down, driving fast to cool off.

The mechanic looked up the specs for filling the R134a, so I'm sure that's not overfilled.

noid · 06-11-2008, 09:52 AM

well you could just realize a bit and see if it helps. But coolant has nothing to do with your ac compressor...

330ci05 · 06-11-2008, 10:17 AM

if you cant get it to work, i'm willing to sell you mine, off my 2005 330ci if your interested, works fine, nothing wrong with it... let me know if you decide to get a new one.... goodluck!

**T.Dot_E30** · 06-11-2008, 10:51 AM

Quote:

Originally Posted by Custom330

Thanks for all the replies. The mechanic tested to see if the system held at (I think) 30psi. When the system held the pressure, it was assumed no leaks. We filled the system with R134a.

Basically, I'm looking for reasons why the compressor wont turn on and stay on.

If the system has the right amount of pressure in it and the a/c compressor is not turning on you'll need to test for power. There should be a wire going to the a/c compressor, it should recieve a signal when you turn the a/c on.

If not then, check your fuses, and trace the circuit (pressure switch, etc.) to find why the a/c compressor is not getting the signal to turn on.

Mikey83 · 06-12-2008, 07:30 PM

30 psi? I test at like 150psi, youll see if it holds soon enough

Dr. Flyview · 06-13-2008, 01:35 AM

Hmm I never thought about checking my fuses, I just assumed I was out of R134a!

chromius · 06-13-2008, 09:08 AM

Quote:

Originally Posted by Custom330

A couple of months ago my coolant level was low, so I topped it up with straight coolant, not a 50-50 mix. Can this be a reason why the ac compressor is not turning on? Something to do with temp?

Basically, I'm looking for reasons why the compressor wont turn on and stay on. Right now I dont turn the ac switch on at all, windows down, driving fast to cool off.

The mechanic looked up the specs for filling the R134a, so I'm sure that's not overfilled.

If it's anything like the e39, then the coolant temp could have something to do with it...On the e39, and I would assume the e46's are similar, the compressor will run in several different modes depending on a number of situations:
-Compressor will not activate if the idle speed increase has not been detected
-If the refrigerant pressure reading from the sensor is either too high or too low, the compressor will be deactivated.
-Evap temp is below 2 degrees C = compressor off
-Coolant temp > 117C = compressor runs in pulsed operation
-Coolant temp > 120C = Compressor is deactivated until temp drops below 117C
-Full throttle below 10mph = compressor shut off for 10sec

I would start by checking the pressure sensor in the receiver/dryer....and also make sure your engine isn't running hot. Those would be the most likely culprits in my mind. Unless it just wasn't filled properly.