4x4 light dosen't work only Different

[gazzer]

Hello thanks 94-explorer 4x4 xlt
4x4 light dose not come on no 4-wheel drive.


I tried my shift motor in another ex it works. Tried a knowingly good motor in my ex nothing.

I did the test with the processor board and no light came on at all. I unplugged the 2-wire harness the longer white one and turned on the key. Pressed the white button and nothing. I tried every combination pressed the button and nothing.
I tried testing the harness wires for power with a simple light tester grounded to the washer plug next to the processor. No power to any connections on the bottom larger jack the one on top the end two connections have power.

Processor? Or switch? Or short? Or ?
I need some help on the next step. Please what should I do?

 

[budwich]

Fuse??????

 

[gazzer]

tested fuse looked unbroken and put the tester on it, it lite up.
Is their another fuse I don't know about>?

 

[budwich]

You can't test the fuse with a light tester, you need a meter. The light tester is telling you that you have power to the fuse terminal. I only have 96 drawing, but they show a fuse in the interior AND one in the power distribution box.... did you check both????

 

[gazzer]

i have a chilton cd for ford turcks, will the chart be on this.?
i pulled the switch and plugged it in and test for power 4 out of 6 had power then i plugged it in and tested the back while depressing the switch no power conection in any of the dead wires. I don't know what that means but I'm hoping it's just the switch. i have no switch to try i have to buy one.

 

[agzaretzka]

Try this...

 

[gazzer]

budwich
I show only one fuse in the box under the hood, for 94 xlt. I will recheck.

agzaretzka
thanks I'll get an ohmmeter and go to work. then I'll get back because I don't know what to do after this but right now this is driving me crazy and I'll probably rip apart anything to fix it.

 

[budwich]

Hey gazzer.... I am probably misleading you a bit with my 96 drawings sorry... yip your 94 truck cd (I am using the same for 96) should show you something about the switch and the fusing.... look under "electronic shift". Anyways, in 96, the switch (its rotary), is selecting resistances which are "read" by the GEM. I suspect that the 94 is doing similar things... may be not.... so it is perhaps possible that your GEM isn't seeing the resistances (broken wire). In 96, the GEM then activates a relay which activates your shift motor.... hopefully your 94 is similar and I have given you some clues on where to look.

 

[gazzer]

Yes I see that the 5-wire harness in the dash explained in the test procedure is an 8 on mine with the 2 buttons. 2H to 4H and low range.
I see the white button on the GEM is it. But I don’t see any indication of a light.
I bought a dash switch and it still no 4x4 no light no noise in the GEM.
Must be a broken wire, or the module.
I can get a module from a junkyard down the street; I haven’t priced them yet though.
I was going to go ahead and get an ohmmeter auto zone has a combo and it’s 50 bucks
I’m not exactly sure how the harness wires are numbered I can only guess from left to right and from top to bottom?
How the heck do they break? I know I’ve smelled burning wires from time to time. And remember the 4x4 switch lights blinking from time to time.
I’ll search my cd thanks fellers

 

[gazzer]

forget it the chilton cd has no information on the electronic shift system.

 

[agzaretzka]

Yes I see that the 5-wire harness in the dash explained in the test procedure is an 8 on mine with the 2 buttons.

The test procedure above is for testing the wiring harnesses AT the GEM; wiring in the dash is DIFFERENT. So expose the GEM in the rear quarter panel and run thru the test procedure. (any generic ohm meter for a couple of bucks, i.e. at harbor freight, will do this just fine).

Until you verify power at the GEM, the effects of the white test button are meaningless.

 

[gazzer]

ok thanks I thought that one of the 3 wire harnesses was the switch lights was the on the dash.

ok I'll do that today. for the GEM

 

[gazzer]

update

1) connect an a voltmeter between terminal 8 and ground . the voltmeter should indicat battery voltage at all times.
results are no current
2) connect an a voltmeter between terminal 7 and ground then turn the ignition switch to run position the voltmeter should indicate battery voltage.
the rusults were nonthing no current.

all other test for the 8 wire pigtail with the ohmeter was 0

five wire harness connector test switch and lights

terminals 1 and 2 depressing the 4x4 2h-4h was about 1 while the switch is being depressed.
terminals 1 ande 3 while depressing the low range switch was the same while the switch was depressed or not.

connect a test lead between terminals 4 and ground, then turn inigtion switch to run position .. no deal nothing no illuminating bars

same thing with terminals 5 and ground. no indicator lights

I hope i did all the test right I used a ground on the washer tank i was sure it was a ground and it was handy.

Please advise thanks
G

 

[agzaretzka]

Then it has to be the wiring; you said you had smelled burning before. So start tracing the wiring back to the source (dash, fuses and battery). Make note of the wire colors for the two power sources (the one that is always hot, and the one that is on with the key) so you can test along the way. The bundle runs along the edge of the carpet, and the part that heads to the shift motor breaks out at the driver's seat.

Check your actual wiring, but the diagram I have shows colors BK/W (A8) for the always hot going to the power distrubution box, and W/P (A7) changing to DB (at connector C200; don't ask me where it is) for the switched power going to the interior fuse box. BK/O (A3) and BK (A2) go to ground; check them too.

AT THE SWITCH, it shows R/Y also going to the interior fuse box, providing power for the lights. Seems the GEM lights them bulbs by providing ground.

Good luck!

 

[gazzer]

thanks for all your help agzaretzka, I think I see what I need to do now. G