'95-'96 to Engage the 4wd full-time
Access the brown wire and make the connections to the brown wire as described in the procedure for the '97-'01 Explorers. However, connecting to the switch will be a little different.
You will need to connect a splice to a power source in order to manually power the Transfer Case Clutch Coil. I used a Scotch-Lok to splice a wire onto the existing Cigarette Lighter circuit, but any power source will work, so long as it can support an additional 5A without blowing its fuse. Make sure to install a 10A fuse in-line as an additional safety. The transfer case clutch coil draws right around 5A on my truck, so a 10A fuse should be more than sufficient.
If you simply want to add 4high, use an SPDT On-On switch. If you want the ability to use 2 low as well, use an SPDT ON-off-ON switch.
Please note: If you want to use a lighted switch on a 95-96 and want to use 2low, you'll need a very specific type of switch (which I can recommend) or a DPDT switch and separate LED (which you can find at radio shack), and the wiring gets a little more complicated. It's not difficult, but it's a whole other discussion for another time. To keep the choices simple, I'll focus on the first two choices I mentioned here.
For the ON-ON switch to add 4 high:
Connect both wires from the splice to the center terminal on the switch. Then connect the wire from the auxiliary power source to the other terminal on the switch. This will allow the system to function normally as it did before, as well as allow you to send power to the TCCC manually when you turn the switch on.
Before putting the dash back together, connect the 4wd switch and take it out for a ride. With the OEM switch set to 4auto, you should feel the system cycle normally. Then, flip your BWM switch on and the system should be locked in 4wd high.
Please note: In order to use 4high, the OEM switch must be set to 4auto first to lock the CAD on the front axle.
For the ON-off-ON switch to add two low:
Connect the wires as shown here: (this shows a DPDT switch, could someone shoot me a drawing of a SPDT switch? I don't have the patience for Microsoft Paint!!!)
Now, before buttoning it back up, try it out. With the OEM switch set to 4auto to lock the CAD on the front axle, you should have one switch on position where the system acts as it did originally (i.e. 4auto). The other on position should lock the transfer case in 4 high. The off position should disconnect the front axle regardless of the OEM switch position.
