Help Me Solve 4x4 problems

[nevadacj93]

Hello everyone I've been trying to figure out my 4x4 System on my 2000 Expedition XLT 5.4 AWD/4x4 I recently acquired this vehicle about 3 months ago and have been trying to figure out my 4x4 problem so any help would be appreciated. So let me start out with the problem once I insert my key and turn vehicle to on position all the dash light come on as usual before starting car and noticed that non of the 4x4 lights illuminate at all however 1 of the lights is supposed to illuminate for a second before going off until 4x4 is engaged via switch however nothing happens here's what I've done

Replace light bulb in cluster for all of 4x4 lights to see if that was problem

Checked all the fuses related to 4x4 and even replaced them regardless

Checked 4x4 Switch the 2 outer wires are for the light bulb on the switch itself and the 2 inner wires are for the 4x4 they are the 2 wires that are not getting power

Had a code for a bad vss vehicle speed sensor so went ahead and replaced it and the sensors on transfer case along with shift motor and it fixed the code but still nothing no power
What so ever

I checked relay in dash also no power and went ahead and swapped them out with ones I know work and still no clicking of relays when turning 4x4 switch however if I unbolt the transfer case shift motor and manually turn transfer case into 4x4 the relays click but still no power to cluster light or switch

Also followed all the wires checking for a break or missing wire or bad ground and everything is fine

So I've pretty much replaced most of the components related to the 4x4 and am at the point where I need help from you guys

Let me know

 

[Bedrck47]

Do you have wiring diagrams for the 4X4 system?

If you do are they factory diagrams or from aftermarket manuals

 

[Bedrck47]

Checked all the fuses related to 4x4 and even replaced them regardless

Checked 4x4 Switch the 2 outer wires are for the light bulb on the switch itself and the 2 inner wires are for the 4x4 they are the 2 wires that are not getting power


I checked relay in dash also no power and went ahead and swapped them out with ones I know work and still no clicking of relays when turning 4x4 switch however if I unbolt the transfer case shift motor and manually turn transfer case into 4x4 the relays click but still no power to cluster light or switch

Also followed all the wires checking for a break or missing wire or bad ground and everything is fine

So I've pretty much replaced most of the components related to the 4x4 and am at the point where I need help from you guys

Let me know

Your troubleshooting skills leave a little bit to be desired


How did you check fuses?

Think about this. Why would you change the relays when you had no power going to them before you changed them? Did you expect to see power magically appear by putting two known good relays in?

You need to find out why there is no power to the relays.

You state that you followed all wires checking for breaks etc. How did you check the wires??

 

[nevadacj93]

I checked the wiring with a multimeter to check for any voltage and also checked wires for continuity the only reason I changed the relays is I have another 2000 Expedition with 4x4 that actually works and swapped it to see if it would work and put the ones that I thought could be bad in the other Expedition and the relays work I just wanted to see if they were contributing to the problem and no I didn't expect to see power magically I just thought it was a good i idea at the time and wasn't spending any money on the relays since my other car has the same ones that work.

Sorry for not clarifying

 

[nevadacj93]

Also the only other thing I can think of is maybe I have a bad gem module thought about swapping gems with my other Expedition but I really don't want to as it's a pita to get it out and then in again.

Also is there another relay other then the one above the left front vent in dash?

 

[Bedrck47]

Again your relays won't work if you don't have voltage going into them You can swap as many as you want but YOU need to find out why you don't have voltage present

Also checking the 4X4 switch for voltage is a waste of time.
You need to check that switch for resistance values.

I will ask this of you again
Do you have wiring diagrams for the 4X4 system?

If you do are they factory diagrams or from aftermarket manuals

 

[nevadacj93]

No I don't have a wiring diagram could use one if u got it

I was just following the wires that go to things related to the 4wd yes I know not the proper way of doing things but I figured at the time switching things from my other Expedition so I could see if my parts were good or not and they work in the other Expedition so either it's a bad wire/wiring or gem is bad however if the 4x4 switch next to radio is bad could that stop everything from getting power ?

 

[Bedrck47]

I have nothing against swapping parts and sometimes it can prove that a part is bad But in your case you had no voltage present so swapping parts was a waste of time other than you now know the relays are good. Find out why you have no voltage present

First check fuse #104 in the battery junction box (under hood) check that fuse to see if you have voltage into and out of the fuse. You do not need to pull the fuse to check this This fuse should have power at all times

http://www.expeditionforum.com/threads/fuse-testing-101.24587/

I do have the prints and also the service manual

If you decide on a manual don't waste your money on aftermarket manuals Haynes Chilton etc.

http://www.expeditionforum.com/threads/factory-service-manuals.25089/

 

[Bedrck47]

It would not surprise me if you say fuse 104 is missing If it is it is a 30 amp fuse

 

[nevadacj93]

Checked the 104 fuse its there and getting power and it's not a bad fuse