Help identifying a connector (AC related)

[jblanken64]

I've got a 1988 325iC and the AC doesn't work. I picked up this car last October and when it's cold out, the AC isn't much of a priority. But now that we're already hitting the mid 90's I figured I'd take a look to see what's up. The previous owner mentioned that there were some problems with it and that it may be resistor related. The AC unit doesn't cycle and appears to be charged. Upon removing the console and HVAC panel, I noticed a 3-pin connector hanging down, with a green/brown and a white wire. It appeared to be melted as well. I'm not sure what it attaches to and I've been looking at the wiring guide as well to try and figure it out. I'll try to attach some pics here in hopes that someone can identify this connector. I've already replaced the evaporator temp regulator and AC switches since those were ohm'ing out a little weird.

[e30davie]

I cant help to much with the connector but you can hot-wire the compressor through the pressure switch and see if it works. Put 12v on one side of the pressure switch (thats down near the dryer) and the other side of hte pressure switch should already be going to your compressor. copmressor should kick in and you should get cold air.

My own AC wiring is a bit of a shamozzle and i put a relay on to mimic the above and has been like that for years.

[tomstin]

Get a copy of your wiring diagrams here: http://wedophones.com/Manuals/BMW/

On my 85, there is a green/brown and white wire connector that is the "Compressor Enable Switch" which prevents the evaporator from freezing. The heat / AC control slide lever for the vent has to be in the middle or to the right for that to enable the AC compressor to come on.

[jblanken64]

Thanks. I've been using a manual from there and I found that the GR/BR and WT wires are supposed to be joined at splice S230. It doesn't appear that they are and that maybe this connector is something a previous owner added. I'm still working through it as I'd like the stuff under the dash to be pretty original even if I need to add some type of relay under the hood for the clutch activation.

[jblanken64]

So I made some progress with the connector. At least from what the wires actually do anyway. It appears that the GR/BR and WT wires are supposed to be part of a splice. After I checked out tons of other things, I felt comfortable actually connecting them. This allowed the switch to work and (seemingly) activate the compressor (the engine revs went up and the AC light went on). HOWEVER, I had forgotten to reconnect the lead from the compressor diode before doing so. Everything did seem to work fine at this point. But once I reconnected the diode lead, the wire I used to jumper the wires in the dangling connector nearly melted. I put a amp meter (clamp style) around the wire and it was pulling over 30 amps. So my guess is that the clutch or compressor is bad and really drawing too much power. Thoughts?

[jblanken64]

Ok, it looks like this connector is "supposed" to be plugged into the HVAC slider assembly. The PCB that is in the assembly allows the wires in the connector to be jumpered together when the sliders are in certain positions. However, my HVAC sliders have no PCB and no connector. Looks like a PO removed the PCB or replaced the HVAC sliders with an assembly that didn't have the PCB. So after I replace the compressor/clutch (and move to R134a), I'm thinking I should be able to simply jumper the wires and not worry anymore about excessive power drain. If there's still a huge power demand, I'll probably just added a relay to the clutch wire. In fact, I may do that anyway.