Need a bit of help with thermostat and a/c wiring?

[VintageBMW]

Hi all, well I am getting very close to finally getting this car back together, but am still puzzled about a few things the PO may, or may not have done when stripping the car. I am getting a bit frustrated at some of the stuff he did, but at I am getting closer!

I am trying to figure out the wiring to the 2 thermostat sensors.

Now, I searched the forum and found that the “plug” type connector (first picture below) breaking is a common issue, and that what has happened to mine. I ordered the plug and wires to fix that one, so I think I have it covered.



I also found this thread: http://www.s14.net/forums/showthread.php?18904-Thermostat-temperature-switch-and-wiring&s=

But, I am not sure about the other 2 pronged sensor on the thermostat.

This next picture is of the plug that I think should go to the 2 pronged sensor on the thermostat.



However, I also need an identical connection to my a/c dryer.

I looked at my iX and the connection to the dryer below, uses a plug identical to the one in the picture above. I can only find one of these connectors in the m3.



So, I guess the question is: how do I tell if this goes to the a/c dryer, or the sensor on the thermostat?

Any idea where I would find the other one?

Also, I assume that the wiring from the condenser fan goes to the connection over by the left head light. Seems like a long wire to go that far, so I just want to make sure this plug DOES NOT go to the sensor on the thermostat, or somewhere else I can’t find a connection for?



Again, I apologize for the long thread, and apprecaite all the help.
Don

[drwillb]

The connector you need to identify goes to switch #19 in the first diagram here: http://www.s14.net/forums/showthread...-and-wiring&s=

You can see the detail in post #3 of that thread.

In response to your last question/picture, the connection for your fan is OK. That long harness runs tucked behind the lower portion of the headlight support/front bodywork, there is a recessed channel there. It goes past the fan towards the passenger side and then doubles back to take up the slack.

[jimmyC]

There is a black wire that comes out of the harness that goes to 1 terminal of that switch. The other wire off the switch would go to the AC compressor to operate the clutch. Some people bypass this switch and run the black wire straight down to the compressor clutch. this switch opens at something like 238 degrees to turn off the ac compressor as the coolant is getting too hot.

[VintageBMW]

The connector you need to identify goes to switch #19 in the first diagram here: http://www.s14.net/forums/showthread...-and-wiring&s=

You can see the detail in post #3 of that thread.

In response to your last question/picture, the connection for your fan is OK. That long harness runs tucked behind the lower portion of the headlight support/front bodywork, there is a recessed channel there. It goes past the fan towards the passenger side and then doubles back to take up the slack.

Cool, thanks for confirming the connection for the fan.

You are correct, I am looking for the connector for #19, but what I am not sure of, is if the connector in my second picture above, goes to the thermostat, or to the a/c dryer.

Here is a picture from my iX, that shows a connector, like the one above going to the a/c dryer. So, what I was wondering is: does the connector above go to the a/c or thermostat, and how do I tell?

I can only find one connector like it, so I am not sure what the PO did with them?

Hope that makes sense.

[VintageBMW]

There is a black wire that comes out of the harness that goes to 1 terminal of that switch. The other wire off the switch would go to the AC compressor to operate the clutch. Some people bypass this switch and run the black wire straight down to the compressor clutch. this switch opens at something like 238 degrees to turn off the ac compressor as the coolant is getting too hot.

Thanks Jimmy, so if I am understanding you correctly, you are saying that the connector in picture 2 above would go to the a/c dryer, and I need to find the 2 wires, as you described for the thermostat switch?

Any chance you have a picture?

Thanks,
Don

[TR-Spider]

I feel with you regarding PO...

you may want to search for the
BMW E30 M3-Electrical Troubleshooting Manual
which you can find on the web, very helpful.
From its content:



HTH
Thomas

[VintageBMW]

Thanks for the diagram!

Hopefully I can get this thing all back together and running in the next few weeks!