Electric shift transfer case. Yes, I have one of these things on my Ranger, and yes it has been giving me problems.

When I first got the truck the system didn't work, and I took the high road and did some troubleshooting and got it working. The clutch switch was bad(this will prevent it from going into low range) and the plastic gear was cracked in two pieces inside the transfer case motor. I turned the motor in and for $100 got a rebuilt one, fixed the clutch switch and it actually worked for about a year.

Then started the dreaded "clicking" and not wanting to go in. It would go in sometimes, and sometimes I could turn the engine off, turn the key on, and it would work then. Then it got to where it would do nothing but click. So then I thought about my options;

1. Sensible thing was to go to the junkyard and get a manual transfer setup with a lever. I could keep my auto hubs, knock on wood they still work fine. But I wondered what type of problems I would inherit with a used transfer case, mine was in good shape mechanically.
2. Try to rig it up with some sort of mechanical system. I tried the system using the grease gun hose as a driveshaft going up though the floorboard, this did not work very well, the 4 high position is hard to find and you need something to lock it in position.

3. I had the perfect setup to move the transfer case already, the rebuilt motor I bought. So I thought why not use it? The next post describes what I did.

 

I bought a switch from the surplus center. Any double pole double throw switch, ON-OFF-ON momentary will work. But no one in my town carries them except Radio Shack, and the reviews on the ones they carry were so bad I was afraid to waste my money on one of them. I looked at the surplus center and they had one already setup for my purpose with good 12vdc ratings. It was a little bit more money, but I hope it was worth it. Experimenting with the wires on the battery demonstrates all the sparks that happen when the motor is moved back and forth, so the switch will lead a rough life. Here's the switch I bought.
DPDT-CO 30 AMP MOMENTARY TOGGLE SWITCH

Here's how I hooked it up with a circuit breaker at the battery.



This is all you really need to get the transfer case to shift, if your motor is ok. You can take your motor off the transfer case, cut just the two wires to the motor, and put voltage on the motor wires to see if it moves back and forth. You can tie some longer wires to the motor wires and touch them to a battery charger and see if it moves. You can also make note of which color wire when it's on the + makes the motor go to 4wd, so you know which direction the motor is moving when you are experimenting.

You can actually run a small cable with two wires in it(or two separate wires) up into the engine compartment, and just touch them to the battery terminals to put the truck in 4wd high,, low or 2wd. There is a problem though, I will get to that in the next post.

 

The problem is you do not know where the motor is at. Another problem is putting a full 12v on the motor makes it "touchy". They must not have put a full 12vdc on the motor with the computer. When you hook the switch up, unless you barely bump the switch, the motor will end up going past the 4 high position. It moves very quickly. It's easier to just hit the switch pretty good and put it in 4 low, and then bump the switch back to put it in 4 high. If you don't mind fiddling with it a little bit, this setup is simple and can get you by. But the next thing I did was so simple, it doesn't make sense not to go ahead and do it. That is, hooking up the 4x4 lights in the overhead console so you know what position the motor is in.

The first thing to do is take the panel off on top of the dash on the pass side where the shift computer is located. There are two screws that hold the panel on, and then take the two screws out that hold the computer bracket in place, and wiggle the computer out.

You will see 3 main plugs with wires going to the computer. Leave the square one plugged in, we won't be messing with it. The other 2 are long rectangle plugs, one with 5 wires and the other with 8 wires. Unplug these plugs, and look at the diagram below, find the correct color wires and cut them loose from the plug and strip them back a little bit. Look at the diagrams carefully, if you are like me you will end up counting the number of wires in from one end of the plug and then verifying the colors, my wires are so faded its hard to see the proper colors.



On the 8 wire plug cut the white, orange/white and the yellow/white wires(3 of them). On the 5 wire plug cut the brown/white and the grey wires.

Take a wire nut or butt splice and connect the white to the brown/white and the orange/white to the grey.

On the yellow/white, strip it back so about 1/2" of copper is showing, or put a crimp ring connector on it. Hold the yellow white wire up out of the hole while you put the computer back down in the hole where it belongs. When you go to bolt the computer in place, take the yellow/white wire and put it around one of the screws holding the computer in place so it will get a good ground from the metal dash.

Now with the keyswitch in run, you should get 4x4 lights and 4 low lights when the motor is in those positions, and neither light when it's in 2wd.

 

I just converted a 1988 Bronco. Works well, but had some different problems to overcome in this one.

Hooked up the battery wire and the switch, and ran the wires to the motor. That part worked great, I could hear the motor shifting the transfer case.

Went to cut and tie the wires together at the dash 4x4 computer, and found the lights did not work in the upper roof console. I have taken this off before in my Ranger, and ended up breaking it and had to super glue it back together. I am trying to remember how I was "supposed" to take it off after I broke it, if I remember correctly you pry the map light switches out, and then take out two hidden screws. Not sure on that though.

I didn't want to mess with the console in this conversion. I found it was quicker and easier to add two lights to my switch bracket. Radio Shack was the cheaper place to get the lights, I found two 12v lights there for about $3. I drilled the bracket and mounted two lights beside the switch, one for 4H and one for 4L.

I then ran two new wires from the switch area up to the 4x4 computer. This is the hardest part, getting the wires fished down behind the dash.

One wire from each light gets tied to ground. The other wire from each light gets tied to the two new wires running up to the computer wires.

The 4L light wire gets tied to the white wire on the 8 slot plug. The 4H light wire gets tied to the orange/white wire on the same plug.

The yellow/white that was previously tied to ground is taken off ground and ran over and tied to the white/pink wire that resides in the SQUARE connector on the other side of the computer. Cut the white/pink in the square connector and tie it to the yellow/white on the 8 slot plug.

white/pink is 12v power with the keyswitch on.

yellow/white goes to the motor switch and is common.

white has continuity with the common in 4L mode

orange/white has continuity with common in 4H mode.

Wired this little deviation and it works great.

 

Hello, I am new here. I know this is an old thread, but I have an '88 Ranger with the same problem and would like to wire in the momentary switch, but it doesn't show the wiring any more. Can someone help please. Thanks

 

I ordered the switch and will assume you wire from the motor to the switch to the battery, with a fuse near the battery on the + side. Wondering since my 4X4 high range works, just not the low range, can I spice into the wires for the motor and just use the toggle to get to low and the factory to use high?

 

You can't use both systems. You have to use one or the other. Mine would not go into low range either with the factory setup, and I found that my neutral switch on the transmission was bad, along with the clutch switch ( I had a manual trans). The speed sensor has to read very low or nothing (you are not moving) and the computer needs to see that the clutch is pushed in, and the trans is in neutral before it will let the motor shift to low range.
I worked with the factory system till it just would not reliably give me 4 wheel drive. That's when I just skipped the whole mess and went with the manual switch.

Here is a diagram on the motor wiring. When you do this modification you need to be careful YOU CANNOT SHIFT ON THE FLY with this modification unless you are sure your hubs are locked in. Just to be safe, always STOP before shifting the motor manually. You have to be stopped to shift it into low range with the factory system. Just treat high range the same way. This is just like a lever system on a manual type transfer case now. And it will still work with the auto hubs if you have them and they work properly.

Another thing you need to know. Putting a full 12v on the motor really makes it move pretty fast. So it's best just to bump the switch. The switch you bought should be spring loaded and return to the center. I labelled my switch "2" on one side and "4" on the other side. If you bump the switch in the "4" direction just a little bit, you will be in 4 wheel hi. It may take a little fiddling to get it in 4 hi, since its in the middle. If you keep bumping the switch you will go to neutral, and then 4 wheel low. 4 wheel low is easy to find, it's at the end of the motor travel. So you bump the switch several times til you know you are at the end and you will be in 4 wheel low. And 2 wheel is easy to find, it's at the other end of the motor travel, I just bump the switch several times and I will be sure I am at the end and in 2 wheel high. I then back up about 10 ft and the auto hubs will unlock.
Once you get the hang of it, this system is very reliable, you can actually depend on your 4x4 system.

 

Thanks, I had my wires reversed. I put an on/on switch between the momentary switch because my factory works well for 4wd high. I can flip the on/on to the factory side and if it doesn't work for low I will be able to flip the switch to the new wiring side and be able to get to low. I ran an extra wire and ground the switch to the battery, should still be the same. This will give me the ability to always get to low range. Didn't see your response before, again thanks.

 

I guess if you went to the trouble to pull the motor completely off the computer system and put it in your manual system with a switch, you could keep both systems. Just more complication and wiring.

 

I simply cut the motor wires and ran them along with the computer side to the on/on switch. One side to the momentary switch, the other to the computer. While I was wiring I cleaned the plug coming from the computer to the motor and sensors. It works now, but who knows how long. I wanted this to make sure i can get into low range.

 

Well it works perfectly, almost. I was hoping to be able to use the original when it worked and have a fail safe. I was also hoping that when using the momentary switch that by switching back to the computer the lights work work to tell me where I was. The lights must be triggered by the computer so when the computer goes all the way out I will rewire the switches and do the change on the computer to get the lights to work. Thanks again for this.