i have a 1990 bronco i bought and someone installed manual front locking hubs if i lock them in i have 4 hi but i cant get 4 lo to work also i would like to fix it right so that i can unlock the transfer case so that it will improve mpg i tested the power going to transfer case motor and to the hi and lo switch i have no power going to either of them now i`m stuck i dont know where or what to check next i have some ideas like relays and stuff but i dont know where they would be located any help would be great.

 

the relays should be in the power dist. box under the hood. some of those Bronco's had shift on the fly and some didn't. I don't remember but most had a shifter lever coming up through the floor and you could put it 4x4 or 2wd just by moving that lever.

 

no mine is push button it has no shifter wish it did and i dont have a relay box under the hood the relays are just plugged in and laying there guess they didnt put a box in this model think im going to buy a manual transfer case and skip all the electric b.s

 

that would be your best bet and then at least you would know what wheels are pulling the thing up and down the road

 

If the spirit so moves you, what if you checked all the fuses ,then got to the back of the push button switch and traced the wires by color if you can see them? One of them should have power to it, so when energized it can activate the relay then the motor on the transfer case. I will try to locate a wiring diagram and see which fuse supplies the switch and it's location. In the meantime have a Happy Easter.

It looks like there is a 20 amp circuit breaker located in the fuse panel that feeds power to the 4wd system.
It should be located in the top center of the fuse panel 2nd one down.
While in there , check all the fuses.

 

thanks a happy easter to you too. i have checked them and all fuses are good but with the test light i still dont seem to have fire to the push buttons thats why i was wandering if and where the relay would be for it

 

The relay is most likely activated by the switch because to energize a relay usually doesn't require much juice and the contacts of the relay usually carry the heavy current required by the transfer case motor. There may be a 4 wheel drive module in the system somewhere and I'm not sure, if so or, where it might be located.
Will keep trying to find the exact info on that.

 

A little background here might be helpful; I'm not sure I understood the question. The 4x4 is controlled by the switch on the dash. The hubs lock the front driveshafts to the front wheels. So, it's perfectly possible to have the 4x4 working (as evidenced by the front driveshaft turning) and the hubs no engaged, which means your still in 4x2.
These systems (the t-case end) had to be in neutral and moving under 5 mph to engage; if the light isn't coming on in the dash, I'd (of course) check all the fuses. If memory serves correctly (and there's a lot of alcohol between now and then, so don't hold me to it), the 4x4 relay was pretty well buried in the dash, however, the control module was somewhere near the glovebox, if I'm right.
There was also a sensor for wheel speed which has to be sending the right signal to allow the shift to happen; you might want to check it out.
Just ideas. Of course, I could be completely wrong. Just ask Hanky!

 

That's funny because I was just going to suggest that you ask greasemark ! Being wrong is for all of us who are willing to jump in when we're not absolutely positive, I think! Even if we don't get your problem fixed right away, we have fun and you will probably get it fixed by yourself anyway. Look who is doing the work? It's probably time for Hayapower to come to the rescue, as usual.

 

long time no see Greasemark was thinking that you had a problem of some sort.