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Discussion Starter #1
I know this problem has already been gone over a million times and I've read several threads with relating problems and followed several helpful links on the topic as well. I have the '89 XLT model with a 302 and AOD. It has the electric shift on the fly option. When I purchased the truck, the 4x4 indicator light was on and has stayed on. The 4low light is flashing and has stayed flashing. Depressing the buttons do nothing, but the truck IS NOT in 4-low. The previous owner did install locking hubs. The front driveshaft turns all the time, but I'm unsure whether or not 4-wheel drive is engaged at all when the hubs are locked, especially since neither of the switchs function. I'm doubting it, although it does seem the truck handles shaky and the gas mileage does seem extremely bad for an EFI. (Less than 250 mpg driving normal wiht 33's) From one of the links, I've read to check a switch or "circuit breaker" in the pass. side kick panel and to check and see if there is power to the dash switch itself. If not, maybe resetting the "circuit breaker" would restore power to it? I've also seen to remove the t-case motor and check where the shift indicator is positioned with possibly moving it to see if any reaction occurs. I've also seen that there is a relay or module of some sort near the t-case that could be bad or is not sending power to the switch that I should check. Do all of these troubleshooting options sound like the right roads to take for this problem, or am I fighting a losing battle with a bad transfer case altogether??? Thanks in advance.
 

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I dont really have any helpful answers for you, but if "manual" locking hubs have been installed, the front drive shaft should only turn when they are locked. If they are not locked and the shaft is still turning, then you are at least in 4 hi. Which would explain your 4 hi light being on. Make sure the hubs are free (not locked) and see if the shaft is turning.
 

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Discussion Starter #3
The driveshaft turns when the hubs are set to "free" AND when they are set to "locked."
 

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Discussion Starter #4
Tried spinning the front driveshaft last night by hand. Won't budge, so the transfer case is definitely engaged. I reckon the next thing to do is try to reset the system via the button or "circuit breaker" in the pass. kick panel??
 

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Formerly vt89gtvert
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From what I have read in your discriptions (And I am not a 4x4 expert), it sounds like the sympoms say you are in 4hi. If the front axle is locked, and the drive shaft is turning all the time then unless there is a disconect where the two meet then it is in 4 wheeld drive. If you are driving this bronco on the street and it is in 4hi (Or low for that matter) then you are about to tear up you diff or transfer case, whichever gives first, and possibly both.

Edit for second though:

If you front axel is locked all the time, then you shouldn't be able to turn the front drive shaft by hand without the fron wheels turning. Don't quote me on that as I once again say, I am not a 4x4 expert. Just trying to help, but wouldn't be suprised if a more expereinced members tells me to just stfu.
 

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The driveshaft turns when the hubs are set to "free" AND when they are set to "locked."
the front shaft should only turn when in 4wd whether hi or low...if it is still turning when in 2hi, than you have a problem in the transfer case the lock outs only purpose is to connect "lock" the front axle shafts to the hub, thus causing the front tires to spin.
 

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Discussion Starter #7
I know the driveshaft isn't supposed to spin unless 4hi or 4lo is engaged. Me having locking hubs in the front really isn't the concern. I'm just trying to figure out what has caused the initial problem with the switch no longer working or having power. Something had to have happened to where power was lost somewhere or something and the result is the truck is stuck in 4 hi because of the switches not being able to disengage it. Like I stated previously, the 4x4 light on the dash is on, and 4lo is blinking. Depressing the buttons doesn't do anything. Would a bad transfer case not allow power to the dash switches?? Could hitting the reset button in the kick panel have any effect on resetting power to the system?? I'm just wondering where would be the best starting spot in finding the root of the problem. Thanks, and apologies for not begin so clear.
 

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Discussion Starter #8
Self-tested the shift control module last night and it flashed 4 times meaning that its most likely OK, but I won't rule it out. On a curious note, when you activate the 4wd switch on the dash, does the module click???
 

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You should hear a click from the kick panel when you hit the button. I would say that if you do and nothing is happening you need to check the t-case motor as it might be frozen.
 

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Untill you figure out why the motor isn't working, Unbolt the motor and twist the selector shaft back to 2WD and unlock the hubs. I've had to do it when my shift motor crapped out on me.
 

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Discussion Starter #11
I'll probably do that tonight as a temporary fix. On a side note, will any other transfer case bolt up and work with my AOD, like the NP203 perhaps?
 

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I'll probably do that tonight as a temporary fix. On a side note, will any other transfer case bolt up and work with my AOD, like the NP203 perhaps?
yes...they are pretty universal when it comes to mounting to the trans...but you will need different driveshafts and crossmembers for a 203.
 

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Discussion Starter #13
10-4, thanks for the help. I'll keep yall updated on the situation as it hopefully gets resolved soon....if you care...lol
 

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10-4, thanks for the help. I'll keep yall updated on the situation as it hopefully gets resolved soon....if you care...lol
Or instead of a 203 look at swapping to a 1356 manual, we have several writeups on this. pretty darn simple and it rids you of that pesky electronic 4x4. Ask me how I know...

The Tcase itself (1356) really is a nice strong unit.
 

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Discussion Starter #15
Found a manual 1356 t-case to swap in at my local junkyard. Does the AOD trans. have the bolt holes in the side to accept the shift assembly from the manual t-case??
 
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