1980 911 Temp control/heating system control box wiring

[ericsinaus]

I have successfully connected up the cables to the servo motor and rear red heater flapper box's but I have found that there are 2 wires that are not connected.

Someone previous to me seems to have messed with the car and removed or disconnected wires so Im not sure what goes where.

Can someone provide answers to the following please:

See on photo that there is a white and black pair of wires sheathed in a stiff white sheath that are sitting above the 2 yellow wires. It appear that at one end they run to the left rear red heat flapper box adjacent to the wheel arch.

Q1. What are the function of these 2 wires connected to on the flapper box. Is it a temp sensor or position control micro switch?

Q2. Where do these 2 wires connect to in the control unit. Everything seems to have a plug in it and appears to be connected except for 2 connections at a white plastic socket with square receptacles sitting above the brown wire in the far right right lower corner of the control unit which obviously is upside down.

Q3. If the white black wires do connect here, which colour wire goes into which socket?

thanks

Eric

[86 911 Targa]

Originally Posted by ericsinaus

I have successfully connected up the cables to the servo motor and rear red heater flapper box's but I have found that there are 2 wires that are not connected.

Someone previous to me seems to have messed with the car and removed or disconnected wires so Im not sure what goes where.

Can someone provide answers to the following please:

See on photo that there is a white and black pair of wires sheathed in a stiff white sheath that are sitting above the 2 yellow wires. It appear that at one end they run to the left rear red heat flapper box adjacent to the wheel arch.

Q1. What are the function of these 2 wires connected to on the flapper box. Is it a temp sensor or position control micro switch?

Q2. Where do these 2 wires connect to in the control unit. Everything seems to have a plug in it and appears to be connected except for 2 connections at a white plastic socket with square receptacles sitting above the brown wire in the far right right lower corner of the control unit which obviously is upside down.

Q3. If the white black wires do connect here, which colour wire goes into which socket?

thanks

Eric

Let's see if this helps.



Gerry

[ericsinaus]

Gerry, do you know whether it matters on which connector the white and black wire are terminated

thanks
Eric

[86 911 Targa]

Originally Posted by ericsinaus

Gerry, do you know whether it matters on which connector the white and black wire are terminated

thanks
Eric

Eric,

The connectors have a dedicated function.

It does matter.

Gerry

pm me

[ericsinaus]

Gerry, do you know what colour goes onto which side of the plastic male terminal block in relation to my photo of the upside down unit with the female socket facing up?
Eg. is the white on the left and black on the right? going down into the socket.

Eric

[86 911 Targa]

Originally Posted by ericsinaus

Gerry, do you know what colour goes onto which side of the plastic male terminal block in relation to my photo of the upside down unit with the female socket facing up?
Eg. is the white on the left and black on the right? going down into the socket.

Eric

Typically, connectors that require an alignment are keyed.

Meaning you can only couple them one way.

I'll have a look at your pics, and some others I have in my library
in the morning.

[ericsinaus]

Hi Gerry,

The black & white wires were cut off the connector prior to my ownership and this is how I found the wires loose as you can see in the photo and I realise the plug only goes one way into the socket. I need help in determining which colour wire goes onto which terminal on the plug.
To keep it simple can you describe this in relation to the upside down socket in the photo. Eg. The black wire makes contact with the left or right contact in the socket.

thanks

Eric

[ericsinaus]

Gerry.

Sorry, today I actually connected these 2 (black & white) wires (that look the same as those coming from one of the rear heater flapper box's) to that socket on the far right side (above the brown wire) while I was waiting for your reply. I found I could not start the car! I have a cobra security dead mans switch system (Its a pain in the arse actually) I went to start the car and no luck. I figured the only thing that I had done was solder those 2 wires onto the socket and plug them together. I ended up pulling the plug out with the end of a screw driver from the front once I took the rubber handbrake cover off. The car started after that so buggered if I know what goes onto that socket. Whever installed this security ignition system must have cut these wires off and I have no idea why these 2 separate things should affect each other.

May be you could tell me what actually plugs into this end socket? Is it the wires from the temperature senser?

thanks

Eric

[Skip1]

Eric,

Gerry helped me work through a lot of my Auto Heat issues as well. I note that yours is a 1980, whereas mine is an 84 Targa. That said, on mine, there were a couple of wires that I believe may speak to your issue. If memory serves, the white sheathed set comes from the temperature sensor in the driver side flapper box (goes through the body behind the drivers seat), and more or less allows the flaps to open once the heat exchangers have reached an appropriate temperature. The other wire was grey on mine and goes to the cabin temperature sensor (mine is on above the rear view mirror). This wire runs on the passenger side floor (left side) towards the front fire wall and then up somewhere. I have additional pictures at home with the connectors if memory serves (one is square and one is eliptical in shape is I remember correctly). Now as for your security system, can't really comment as I don't have one. Will try to post some additional details later today if I get a chance.

[Skip1]

OK, so here is the best picture I have of the wires (black and white) that I believe you're referring to. The two wires seem to be those heading to the flapper box temperature sensor. The black wire appears to be on the same side as the locking tab for the connector (which based on the orientation of your picture is the square connector (furthest forward below brown wire), left pin. Will try to find a better picture, but... The grey sheathed wire seems to have the rounded connector, which is the in cabin temperature sensor on my car.



Hope this helps.

[Nerodino]

So can anyone help me please?
I have an 82 930 and I have my heater control unit off to replace the fore and aft fuel pipes (don't ask ha ha ) so while I'm in here!!
The two brown wires which the OP has connected to the two yellow wires?
On my car those two brown wires are not connected to anything and I have no such pair of yellow wires anywhere in sight......what do they do and where do they go?
Thanks