After following a poorly adjusted diesel truck for several miles in traffic,(Chevy) my wife exclaimed "I wish this truck had an on/off switch for the A/C so you can put this thing on Max A/C and keep the stink outside without running the A/C". She is spoiled. Her 92 Mercury Tracer has the ability to turn the compressor on and off, our 96 S10, as well as the 97 GMC did as well. I began the process by using the 'search' function on this excellent website and after a few rounds of search, found the info needed.
These guidelines are not intended to cover every late model F series truck. This applied to my 1999 F150 SC XL. **** The following post is for entertainment use only and is not intended for all applications or skill levels. Viewer discretion is advised. May void factory warranty ****
Disconnect the battery and turn the headlights on to remove any electrical charge remaining. Remove the plastic bezel which surrounds the climate control and radio area. (Gently pry using a smooth bladed butter knife and work your way around the outside) There are 4 clips which hold the bezel in place. Remove the radio using the special U shaped tools for the Ford radio systems. (most autoparts stores have them, but you can also use very small screwdrivers...for minimal damage buy or borrow the correct tools tho...) Behind the climate control vent selector switch is a 4 wire connector which will require that you lift up the slide retaining clip. Remove the connector and locate the purple wire. Unwrap enough of the electrical tape to give yourself some wire length to work with (2") Cut the wire in half. Using wire of the same gage, (20ga) solder and apply heat shrink tubing over the solder joints. (Do not use electrical tape!) The extension lengths should be long enough to reach the position where you are going to mount the switch and indicator light (or lighted switch combo) Find a suitable ground and run another wire for the ground side of the light function. (I chose to use a Radio Shack pushbutton panel switch and a blue 12v snap-in light) The mounting took place in the bezel under the panel vent near the driver. In addition, I used quick disconnects on the light and switch leads so I could remove the bezel unit in the future without cutting any wires loose. I can now turn the compressor off and on as needed. When 'on' the blue light is lit in any of the vent positions where the A/C would normally be active, when 'off', of course, it does not light.
The following is a parts list of what I used for this project:
1) Radio Shack push-on/push-off switch #275-617
1) Radio Shack blue snap-in 12vdc lamp assy.
#272-335C
24" of multi-strand 20ga wire and 6" of heat shrink tubing.
You may want to use a resistor to drop the voltage to the bulb, it may prove to be too bright at night for some locations on the dash......jb

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99 SC Sport XL, Silver everywhere
4.2 auto, 3.55 rear gear
Split bench w/drivers side raised 2" in back
Stock AM/FM w/2 cheesy speakers
Ford brand bedliner, Mobil 1 w/Motorcraft FL400S filter
DynoMax single in/out muffler

 

I just pulled the A/C fuse, hooked leads from the fuse holder to a switch and remote fuse. I ran the wires from under the hood to under the dash for a hidden location. To revert to stock, all you do is pull out the wires a put the fuse back in the stock holder.

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Badd Andy

2001 Toreador
F-150 Supercab XLT
7700lb, 5.4L, 4R100
Tow Packg, 3.73
DRL Foglite mod
Headlites Relayed
A/C cutout switch
RS 9000's all around
Bug & Wind deflectors
Dupli-color bed
Lund Premier Tonneau
Short rubber antena
98 ANGLER 8.6 Camper
95 Windstar w/replaced head gasket
97 Susuki Bandit 1200
87 Yamaha XT-350

 

Thanks for the ideas! This is a major problem with Ford products with no control for recirculating vs. outside air and AC on/off.