I have a 2001 3.0 V6 4x4 extended cab. 4WD is not working. Not sure if this added to it, or if it just made me notice as I have not used 4x4 since last winter.
I changed out dash lights, and while making sure which ones were out, I blew a fuse. The one that controls the speedometer and some lights. I thought I got all the lights working, replaced the fuse and noticed the 4x4 lights were not coming on when starting. Bulbs are good. So started checking around, and found the power connection pin for the 4x4 control module was completely rotten off. I mean its no longer there. I have a 2001 4.0 4x4 parts truck. I grabbed the control module from that, put it in, and the lights turn on when I start now (improvement) but 4x4 still not engaging. Neither hi nor low. No sounds either. No clicking no nothing.
Are the control modules the same with a 3.0 and a 4.0 is my main question.
The part numbers are exactly the same. But when it did not fully work, I looked closer and noticed there is also a data code and these are different.
Thanks

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2001 4x4 3.0 V6 extended cab 4 door off road

Check to see if you have power to the transfer case motor and if you do check the motor connection they corrode.

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barneycat11 2006 FX4

The good, the bad, and the ugly.
Checked wire harness connection at the transfer case motor. Disconnected it. There was corrosion. Checked for power with key off. Nothing. Checked with key on, and there was power to 4 of the 7 pins. Cleaned it up with mass air flow sensor cleaner (have it, and think its safe to spay on connections). Let it dry out completely. Reconnected it, and YES it went from 2 wd to 4 wd hi, and then it went to 4wd low. Thinking AWESOME.
BUT now its stuck in 4wd low. Start truck, put it in N press brake, switch to 4wd hi, or 2wd, control module making clicking sounds. 12 clicks then stops.
Have tried tapping motor with hammer, nothing.

So now, there is progress, but now I can't drive the truck.

Questions, is it possible the control module from the 4.0 engine is wrong?
Is the motor bad?

In any case, THANKS for the direction to the corroded connection, This is progress.

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2001 4x4 3.0 V6 extended cab 4 door off road

OK, update.
I think the transfercase control module from my parts truck with a 4.0 does not match the control module I need for the 3.0 in my truck. Not sure if its the actual engine size, or if there are different ones based on when/where made.
I know the original one is bad. A power feed pin in the module is completely rotten, gone, not there. Jumped out the power to it, and it still did not work. Another wierd thing, the rest of the pins all look almost as good as new. No rot.
With the module from the 4.0, and the connection cleaned for the connection for the motor the module clicks when changing from 2wd to 4wd. But as I said, the 4wd low light would not come off. But I took it for a ride, and it was NOT actually in 4wd at all. Plus the speedometer was not reading correctly. Reading 10 MPH when doing at least 35.
Disconnected wiring from module and motor, waited 10 minutes, reconnected, and 4wd lights flash when starting, but go off again, and speedometer reads correct again.
Going to order new control module.
all part numbers on them are the same except the data code. 00301 on the one from the parts truck, and 00346 on the broken one.
Please let me know if what I am doing/saying makes sense, and if you have any comments or advice on this project.

Thanks

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2001 4x4 3.0 V6 extended cab 4 door off road

I read a bunch of listings on the control module, any recommendations on where to get one on line? Checked local stores, none had it in stock. Part stores were about 180. Dealer, 260 or so. But none in stock. So if I need to wait, will get on line for hopefully less.

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2001 4x4 3.0 V6 extended cab 4 door off road

You should check the motor connection again scrape the pins and use a good contact cleaner.I would take the motor off and see if it works right in all ranges you can also switch the transfer case by hand with the motor out.

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barneycat11 2006 FX4

Checked motor connections, and pulled motor. The transfer case rod spins to 4wd hi and 4wd low well.
Grounded motor with wire clips, check with test light and it was grounded. Plugged it in and switched the truck into 4wd. Nothing. Pulled motor from parts truck and tried the same, nothing.
Also called around. The control module is a special order. The dealer needed the last 8 digits from the vin of the truck to look up the part. This leads me to believe even the exact same year make model may have different control modules. The one I have is from the same year, but its from a 4.0 engine. Not the 3.0.
Maybe I'll stop by the dealer today and see if both vehicle vins take the same control module before spending the 160 for a new one.
Any other thoughts?

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2001 4x4 3.0 V6 extended cab 4 door off road

After checking the motor, finding a wire diagram, and tracing all I could, I could not find anything wrong.
First control module was definitely bad. A power pin completely wrotten off, gone. Start truck, no 4x4 lights, nothing.
Put the one in from my parts truck (different engine but same year) start truck and 4x4 lights flash. Turn to 4x4 hi, some clicking from the control module, the 4x4 light came on, but not actually engaging. And light would not go off when put back to 2 wheel.
So I knew the first control module was bad. So I bit the bullet and went and bought a new (well refurbished) one from Autozone. $200 after sales tax. Put it in, reconnected motor and IT WORKS.
Thanks for the help and assistance. Really appreciated.

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2001 4x4 3.0 V6 extended cab 4 door off road