1990 4x4 help!! please

[lorennits]

Hi, so I bought a 1990 ford ranger 2.3L 5 speed manual with the electric transfer case. I have been trying to fix the four wheel drive for about 2 month now and I'm at a halt.
To start I have replaced the transfer case motor and the push button switch. The fuses are all the. the module behind my seat seems to be good I think, when I press the button on it the red light flashes 4 times. For the actual push button switches they are both constantly light up but very dim and when I try to press them I get no response and hear nothing at all. I have tried everything that I can think of and still nothing. The transfer case seems to be decent because when I replaced the motor I manually put it in 4x4 and both axles spun just fine. has anyone had this problem or know anything I can do to fix it. I tried to put all the information in this post to help you understand what's going on. thank you

 

[franklin2]

That system is notorious for not working when you need it. I got mine partially working for about a year by finding some corroded connections in some connectors laying on the driver's side fender under the hood. The driver's side tire is bad for throwing water and road dirt up in that area.

But after about a year, it start giving trouble again. So I just converted mine to a manual toggle switch under the dash and it always worked after that.

 

[franklin2]

Here's some links in the tech section.

Checking 4WD Shift Module Circuits (1994-Older) - The Ranger Station

There are three wiring connectors connected to the electronic control module: the eight-wire pigtail harness connector; the five-wire harness connector; and the eight-wire harness connector. To check the integrity of these circuits, disconnect the harnesses from the electronic control … Continued

www.therangerstation.com

Ford Ranger 4x4 Module Diagnosis (1994 & Older) - The Ranger Station

By Chris1044 If your 4WD Ranger has a push button 4wd system (automatic, no manual lever), than it’s going to have a 4WD Shift Module mounted somewhere in the cab. The photo above shows one mounted under the jumpseat … Continued

www.therangerstation.com

 

[lorennits]

That system is notorious for not working when you need it. I got mine partially working for about a year by finding some corroded connections in some connectors laying on the driver's side fender under the hood. The driver's side tire is bad for throwing water and road dirt up in that area.

But after about a year, it start giving trouble again. So I just converted mine to a manual toggle switch under the dash and it always worked after that.

this sounds like a good idea do you haven videos or articles to help me make the conversion

 

[franklin2]

Not really, it was my own homebrew thing. But from your experiment you did with your motor, I think you will understand how this works.

All I did was buy one of these switches.

DPDT-CO 30 Amp Momentary Toggle Switch GlideForce SWT-TOG-MOM-4W | Toggle Switches | Switches | Electrical | www.surpluscenter.com

DPDT-CO 30 Amp Momentary Toggle Switch GlideForce SWT-TOG-MOM-4W, Toggle Switches, DPDT-CO 30 AMP MOMENTARY TOGGLE SWITCH, 30 AMP 12 VDC REVERSINGGlideForce,SWT-TOG-MOM-4W ,

www.surpluscenter.com

I mounted the switch under the dash with a bracket. One set of terminals gets power and ground. I ran a wire out to the battery with a 30 amp circuit breaker hooked directly to the battery + terminal.

The other set of switch terminals gets two wires that run to the shifter motor. I found it easier to run cable with two wires already in it. You snip the two wires going to the motor, and hook these two wires from the switch to it.

Now you are simply putting 12v directly to the motor to move it. The switch just switches the polarity of the 12v to the motor so it changes direction. You can see how the switch does that with the "X" jumpers on the back of it.

Warnings about this conversion.

1. You MUST BE STOPPED to use this. No more computer to do any thinking for you, it's much like a lever on the older systems. You could theoretically engage 4x4 hi if you were confident your hubs were locked in, but I would not do it. It's too easy to hold onto the switch too long and accidentally try to engage 4x4 low. It's just simpler and safer to stop before trying to engage 4x4 with this.

2. I am assuming the computer system put something less than 12v to the motor. The reason I say this, the switch is very touchy. All you have to so is bump the switch a couple of times to get it to engage. All I ever do is bump it a little bit to engage 4x4 hi, and then bump it several times to get 4x4 low. You can feel it engaging sometimes. And once it awhile you might not get it all the way and when you go to take off it won't move and you get a slight grind. That means it's not quit in all the way and just another bump of the switch takes care of it.

What I did later on was wire in the 4x4 lights and the 4 low lights on the console. So I could bump the switch and watch the lights, and then it helped me know where I was at. If you get the first part working and your confidence built up on that, then the lights might be a stage two wiring exercise.