I have a 2003 F250 v10 with a automatic tranismission. I have no four wheel drive it is the electronic on the fly system with just the little turn **** on the dash when you turn the switch nothing happens it does not engage in high or low its like there is no power gettin to the switch or the motor that engages it any ideas??

 

Does the 4x4 light come on?Could be a fuse.Someone will give you the correct fuse number to check.If you have the light,are your vacuum lines to the hub intact?

 

when you turn the parking lights on the switch lights up but that is the only thing it does i have checked all the fuses and they are all good i am lost is there some kind of sensor on the transfer case could that go bad i saw a forum somewhere about a 36 dollar sensor for a transfor case that causes problems like this but i am not sure where i saw it at

 

Im having the same Prob. Im going crazy. Someone told me its the transfer case shift motor. I replaced it and thats not it. I have been told it may also be the vacume solinoid. But im not sure. I will keep an eye on your thread. I hope someone has an answer

 

I hope so to it started snowing here yesterday and its only gettin worse!

 

I'm going to bump this up for you so it doesn't get lost.

 

dont you gots manual locking hubs?

def check out vacume solinoid

 

Won't be that. If you changed your transfer case motor and that's not it then you're not getting power then.

 

I have checked all the fuses. I did get stuck. I did drive kinda hard to get out. All seemed fine. I parked the truck the next morning I started it to pull it in my barn and the 4Wheel did not work.

 

OK, one step at a time.

Is the 4x4 indicator in the console display functioning. To test this, do the following. With the key off, push and hold the odometer reset button. Turn the key on and wait for the odometer display to say "test", then release the button. All of the gauges will sweep to the max and return. Push the button again and the odometer display will read "bulb". All of the bulbs in the display should be lit. If the 4x4 indicator is not lit, then the 4x4 indicator is not working and it will be hard to diagnose the problem further.

If the 4x4 indicator in the console display is functioning as tested above, then the next question is when you move the dash switch to 4x4, does the 4x4 indicator come on. If it does, then the 4WD module, relays and transfer case motor are probably functioning and the problem is probably in the hubs, the vacuum lines, the vacuum solenoid, or the vacuum pump.

If the 4x4 indicator does not come on, and is known to be working based on the first test, then your transfer case is not shifting. This could be a bad dash switch, a bad 4WD module, bad shift motor relays, or a bad shift motor, or fuses to any of the above. The most common cause of this are the shift motor relays. They are in their own relay box on the passenger side of the engine. Check the contacts and wires for corrosion. Check the wiring to the box for chafing. Swap the two relay positions and try it again. If it shifts in then, if probably won't shift out and you should replace the relays.

If none of those work, get back to us with what you did and what happened and maybe we can figure it out further.

 

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Good suggestions so far. Follow David Chamberlain's post, and report back.

 

I also have that problem (5.4 ltr ,2003 ) .I checked fuses and vacume as requested .I will now check shift relays .My 4x4 works but it takes a long time or not at all .When I first start the vehicle up, 4x4 might come on or off with the switch turned on or off before vehicle is started ???

 

I have a 1999 F-250 Super Duty to. I have the same problem. My four wheel drive worked fine one day and the next day nothing. No lights nothing. I have checked all my fuses they are fine. I have replaced the two relays for the electronic shift on the fly. They also have done nothing. I have also took the switch out for the 4x4 and tested to see if I got power. I did not get any power to the switch inside the truck. I also pulled the wires off the transfer case I'm not getting any power there either. I checked to make sure I had a good ground before I checked that. The next thing I am going to try is Ive been told there is a four wheel drive module. I think I have found it. Its on the passenger side. There is a plastic panal you pull off. Its down by your where your feet sit. So Ive been told that a module for the 4x4. I'm going to replace this. I'll post back and let you know how I made out.

 

As mentioned above by dchamberlain in one of his points, it could be as simple as the plug on the back of the switch has become unplugged (how do I know this - it happened to me). I started at the shift motor and relays and worked my way back to find out that the plug behind the switch was disconnected (not loose - disconnected completely). Check the simple things like the switch plug at the back and also the switch itself and follow those troubleshooting points above.

 

The switch could be unplugged or the light could just be blown.


Turn to 4hi and get out and check if you can turn the u joints. If you can, probably a vacuum leak or bad seals. If you cant turn them you most likely have a transfer case issue.

That should let you know if the switch is doing anything.