81 F100 AC wiring harness ??

[Gary Lewis]

Ok I "think" I may have found the answer I need on the cut wires of all places LMC site.

http://www.lmctruck.com/icatalog/fd/full.aspx?Page=141

It looks like the fan switch is the same for AC and non-AC systems as does the plug/pig tail.

My thinking has been and still is you un-plug the BR/OR looped wires and plug this AC harness in to the 2 looped wires.

The AC harness has a fan switch plug that after unplugging the non-AC plug from the fan switch you now plug this AC plug into the fan switch.

If this is so, still need someone to confirm the 2 plugs, I can buy a new pig tail and splice it onto the wires but brings up another question.

What is the pin out of the wires to the switch?

Anyone have that other page (page 151?) in the link for the switch pin out and does it include the AC harness?

Thanks

Dave ----

Dave - I'm not sure I understand your questions. But, let me try to answer.

First, you are right that the same switch is used for all forms of heat and A/C. I added a bit to the HVAC/Integral A/C page and the Part Numbers tab that confirms that.

Second, you asked for the pin-out on the connector, and that is show on Page 101 of the Electrical/1981 EVTM/Component Testing section.

Does that answer the questions?

[FuzzFace2]

Dave - I'm not sure I understand your questions. But, let me try to answer.

First, you are right that the same switch is used for all forms of heat and A/C. I added a bit to the HVAC/Integral A/C page and the Part Numbers tab that confirms that.

Second, you asked for the pin-out on the connector, and that is show on Page 101 of the Electrical/1981 EVTM/Component Testing section.

Does that answer the questions?

It does and does not.

The testing of the switch gives wire color and where they go on the switch but none of the colors are what is in my AC harness and cut wires.

In this link http://www.garysgaragemahal.com/ac--heater.html 2nd picture down has a note to look on page 151 for the switch pin out. I wonder if the colors are different in that one?

It is strange that most of the cut wires are brown/white and that 1 green/purple (PSI switch wire) but I don't see how that ties into the fan switch to turn on the AC compressor?

Now that I have the pin out for both AC and non-AC switch I can see what my truck has.

The hunt goes on!

Thanks

Dave ----

[ArdWrknTrk]

It does and does not.

The testing of the switch gives wire color and where they go on the switch but none of the colors are what is in my AC harness and cut wires.

In this link http://www.garysgaragemahal.com/ac--heater.html 2nd picture down has a note to look on page 151 for the switch pin out. I wonder if the colors are different in that one?

It is strange that most of the cut wires are brown/white and that 1 green/purple (PSI switch wire) but I don't see how that ties into the fan switch to turn on the AC compressor?

Now that I have the pin out for both AC and non-AC switch I can see what my truck has.

The hunt goes on!

Thanks

Dave ----

Dave, I do know one difference between AC and non AC is the blower resistor.

I have now modded my non AC harness to take the AC resistor.

So maybe your wiring has some change there, where non-AC systems don't have a "max-AC" position?

[FuzzFace2]

Dave, I do know one difference between AC and non AC is the blower resistor.

I have now modded my non AC harness to take the AC resistor.

So maybe your wiring has some change there, where non-AC systems don't have a "max-AC" position?

I am using the full main & AC harness from the parts truck that had AC, just moved it from 1 truck to the other. I am even using the rear harness that runs along the frame (duel tanks) and the tail light harness.

There is some thing with this AC harness I just cant get my head around.

I think the next step is to pull the AC harness out of the truck, lay it on the floor and take a picture or 2 and where it plugs into the extra main harness so everyone (me) can see this better and maybe under stand what I am seeing.

Peteponies, being your dash is open can you see what color the wires are going to the fan switch.

Thanks

Dave ----

[FuzzFace2]

Dave - I'm not sure I understand your questions. But, let me try to answer.

First, you are right that the same switch is used for all forms of heat and A/C. I added a bit to the HVAC/Integral A/C page and the Part Numbers tab that confirms that.

Second, you asked for the pin-out on the connector, and that is show on Page 101 of the Electrical/1981 EVTM/Component Testing section.

Does that answer the questions?

I have to bring this up again as I have to get to the bottom of the cut wires.

On the web page "component testing" page 101 has the pin out of the plug for the blower switch.

The wire colors and plug shape do match a plug/colors I have on the truck.

Now page 100 has a picture of a plugs wire pin out that looks like has the right colors of the cut wires I started this thread for but I do not know where this plug is (cut off?) and the big one - where dose it plug in to?

The picture does not say where it might be so I am at a loss!

Please help

Dave ----

 

[Gary Lewis]

Dave - I'm not sure I understand your questions. But, let me try to answer.

First, you are right that the same switch is used for all forms of heat and A/C. I added a bit to the HVAC/Integral A/C page and the Part Numbers tab that confirms that.

Second, you asked for the pin-out on the connector, and that is show on Page 101 of the Electrical/1981 EVTM/Component Testing section.

Does that answer the questions?

I have to bring this up again as I have to get to the bottom of the cut wires.

On the web page "component testing" page 101 has the pin out of the plug for the blower switch.

The wire colors and plug shape do match a plug/colors I have on the truck.

Now page 100 has a picture of a plugs wire pin out that looks like has the right colors of the cut wires I started this thread for but I do not know where this plug is (cut off?) and the big one - where dose it plug in to?

The picture does not say where it might be so I am at a loss!

Please help

Dave ----

Dave - The connector on Page 100 is the one that goes into the A/C Heat Function Selector Switch, meaning the one with the horizontal lever next to the fan switch. Here's the drawing from Page 100 showing the circuits: 181; 182; & 348.

And here's Page 83 showing that switch and the same circuits.

[FuzzFace2]

Dave - The connector on Page 100 is the one that goes into the A/C Heat Function Selector Switch, meaning the one with the horizontal lever next to the fan switch. Here's the drawing from Page 100 showing the circuits: 181; 182; & 348.

And here's Page 83 showing that switch and the same circuits.

I was working with someone else as he looked over his truck and your links for the 100th time and seeing page 145 the light bulb went off!

I even went out to my garage dug thru a bin and found the control panels I got from other members as sure enough there was the socket for the wires.

When I looked at them before I was looking for a large socket like for the fan & tank switches.

The only thing that throws me now is the pin out.

The "terminal locations" picture is a square and you can see it is inline.

I think I can use spade connectors but I don't know what color goes were on the selector switch.

Any one have the HVAC panel out and can check wire colors top to bottom on that plug that would help a bunch.

Thank you all for the help

Dave G.

[Gary Lewis]

I was working with someone else as he looked over his truck and your links for the 100th time and seeing page 145 the light bulb went off!

I even went out to my garage dug thru a bin and found the control panels I got from other members as sure enough there was the socket for the wires.

When I looked at them before I was looking for a large socket like for the fan & tank switches.

The only thing that throws me now is the pin out.

The "terminal locations" picture is a square and you can see it is inline.

I think I can use spade connectors but I don't know what color goes were on the selector switch.

Any one have the HVAC panel out and can check wire colors top to bottom on that plug that would help a bunch.

Thank you all for the help

Dave G.

Dave - I can check my wiring on Friday, but won’t be in the shop until then.

[FuzzFace2]

Dave - I can check my wiring on Friday, but won’t be in the shop until then.

That is fine as I don't think I will be out in my garage till the weekend and will most likely be working on the bed but I will need that information sooner or later.

I also need to pick up some small vacuum line and look up the routing of the control hoses before I can mount the HVAC panel.

Thanks again for your help.

Dave ----

[Ford F834]

I was working with someone else as he looked over his truck and your links for the 100th time and seeing page 145 the light bulb went off!

I even went out to my garage dug thru a bin and found the control panels I got from other members as sure enough there was the socket for the wires.

When I looked at them before I was looking for a large socket like for the fan & tank switches.

The only thing that throws me now is the pin out.

The "terminal locations" picture is a square and you can see it is inline.

I think I can use spade connectors but I don't know what color goes were on the selector switch.

Any one have the HVAC panel out and can check wire colors top to bottom on that plug that would help a bunch.

Thank you all for the help

Dave G.

Dave, I *just did a re-pin from the early style square connector to the later style flat connector for my 1981 (upgrading to a 1985 HVAC controller). I will do a how-to web page on it, but for now you can see it in my build thread. I didn't use spade connectors, I just released the terminals out of the square connector and snapped them into the flat connector. I don't know what your time frame is like but I will be going to the junkyard Friday morning if you need/want a flat connector to re-pin.

Here is my post with a picture of the wire color order. Note that the brown/white wires (2) are fused within the loom so the order on those does not matter:

http://bullnose-enthusiasts.12971.n8.nabble.com/1981-straight-six-manual-4x4-project-tp1312p3609.html