I have an 1997 BMW M3. My AC stopped working. there are no lights. However, it started again briefly. what

Question

How can i fix this problem. i thought it was a fuse, but when it came back on, it must be something else.

Thank you all for your answers. In my case, the panel is black. It is completely turned off. There is no fan or hot air. Nothing - just like the switch was disconnected. However, as I was driving, it magically turned back on. I parked the car and later got back in and it was "off" again and has not turned back on yet. Thanks for your help!

Let me add additional details: I have been able to get the air-conditioning to come on intermittently. I am not sure how though. Perhaps simply letting the car sit for a day. However, the last time I drove it, I used the ac the entire time. When I came home and opened the hood, it seems excessively hot near the front of the engine. Close to the fan and windshield washer bottle. The gauge in the car was normal. What do you think?
Thanks in advance!

Answer 1

It may be the control panel.

Answer 2

The control panel is the problem. I have a 97 M3 myself, and the E36 3 series are notorious for this problem. There is a capacitor on the circuit board that has a weak solder joint. When it finally gives way, the whole panel goes dark, and the system defaults to heat (in case it happens in the winter, I guess).

Anyway, there are several ways to fix this problem:

1) Get a replacement panel and swap the old one out. This is an easy job. In the sunglass cubby, on the top side, is a hole. Put your finger in and you will feel a tab. Press the tab, and at the same time pull on the on-board computer; it hsould pop right out. Next do basically the same thing for the climate control panel. There are two connectors (if I remember correctly). Unplug the old panel and plug in the new one. Everything just snaps right back into place.

2) Fix the old one. There are several sources online who will repair your panel for you. Check Bimmerforums.com. You will have to ship your panel to them, they fix it and send it back. Or, you can fix it yourself. There are several how-tos online that tell you what you need (a certain capacitor that is available from RadioShack and soldering tools), and step-by-step instructions.

3) Do what I did and rig it. The big connector on the back of the control panel is right next to the bad solder joint. If you wiggle it around, you will be able to see the panel flicker on and off. Figure out which way you need to move the connector, and wedge something in between the connector and the exterior of the control panel. I used a wood shim like those used for doors and windows (You can get a whole package of them at Lowe's or Home depot for about $1). Just break off a little piece, and wedge it in there. You will have plenty in the package to make mistakes with, so take your time and break off a piece that is the perfect size.

I did this almost two years ago and have had zero problems since.

Hope this helps and good luck!

Answer 3

The control panel of the E36, both the manual and digital, are known to fail at some point in the cars life. For some it's sooner than others. The replacement is definitely a do-it-yourself but the part isn't that cheap. Be sure to check the forsale forums in Bimmerforums.com and see who is parting out any E36's Just ask if it's digital or not and if all pixels are working!

Answer 4

How is the AC "failing"? Is it just blowing warm air or there's no air at all? Or is the fan coming on and off, high and low?

If it's just blowing warm air, it might be you're just low on refridgerant. If the refridgerant pressure is too low, it compressor will not kick in. It might be you're just borderline now; so it's getting cold periodically.

If you have an a fan that goes up and down in speed erratically, there's a component called the final stage resistor. That might have gone bad.

Answer 5

It may be the control panel, but it could be low refrigerant causing the compressor to run briefly, shut down, then not come back on for a while, then repeat the process. Check there first.

Answer 6

just check the air con relay.or some loose conections from the main fuse box.
Please check whether the condensor fan is in working condition.
BMW car,s air con system works in a package deal.for safety reasons.some get upset,but the car saves 4 u.
if refrigerant is low-it stops.
if fan not working it stops.when compressor on heavy load it stops.
when relay/switch or wires faulty it stops.
when temperature hig it stops.
All this is made to safe heavy damage to engine and wiring of the car.