Driving me nuts, tested everything exactly how the factory says to check and it for code C2112 said the 4wd module was bad, bough one from the dodge dealer and installed it butt it still keeps setting a hard code C2112 for the front diff sensor circuit. I even went further and checked ohms and voltages both plugged in and unplugged and such with my same year truck that the 4x4 works perfect (for a stupid electric shift anyhow). I still get the service 4wd and no 4wd, every time I clear the code it is back on instantly. I bought the truck at auction and whoever owned it looks like they were chasing the same problem, it has a brand new t-case electric motor. It is a 2011 1500 5.7 hemi.

I had an 08 that had random 4wd problems. Mine had the auto 4wd option and if you use that option it only worked once then quit. It also didn't consistently switch to 4wd or 4low and would just flash the 4wd light. I took it to the dealer and replaced the t-case shift motor and that worked fine for a short time. I took it back and they warrantied that motor and the same problem, worked fine for a short while then killed that motor. They ended up replacing the shift motor again under warranty and changed out the TIPM and the problem was fixed. Of course it snowed every single time I took it into the dealer, and it rarely snows here lol.

Have you checked the make sure it is not a mechanical failure?

This one is not got auto 4wd, it has 2wd 4lock and 4 low. I can't imagine any mechanical failure where it would set a sensor code instantly upon clearing the code even with the key off.

Is there any other codes? Also make sure that is the right transfer case shift motor.

That's the only code in the power train or anything I can find related in the least (has a loss of comunication with the radio code in some module I came across). I don't get why the heck they had to go back to unlocking the front hub in these bass tirds, or even electric shift for that matter, the manual shift in my dakotas was way faster and easier to engage than this electronical crap. My 4x4 daks barely got any worse MPG than my 2wds and I always keep very meticulous track of what they do. I followed the factory diagnostic chart very carefully about 10 times and it says the solenoid is bad, both the one off this truck and my personal truck work on my truck and neither works on this one. Looking at the wiring diagram none of the wires for this circuit go to the t-case motor, they all go direct to the locker thingy.

There is a transfer case module that could act up. I believe it is under the dash near the hood release if I remember correctly.. Maybe check the wires and swap it with another truck. Dorman makes a reman.

I bought a new one from dodge, didn't do nuthin different.

Is there a front axle disconnect? If so and that for sure is good I would check the wires from there to the module. Have you tried leaving it in 4wd and clearing the codes? Obviously if its immediately hard faulting there is something it does not like.

That front axle disconect is what the code is supposed to be for, there is a sensor in it and the sensor circuit is where it thinks there is a problem. Both wires for that show the proper voltage plugged in and unplugged. I replaced the mini harness thinking maybe something was not making contact in there but that harness works on my truck and still gets the hard code on this one.

Did you ever unbolt the disconnect motor and try to operate it? Just thinking out of the box here. If for some reason the motor can not get to its requested position the sensor relays that its not there and hard faults.

Turns out it was the plug in on the transfercase motor, the new motor the previous owner installed kept me from looking too hard in that area plus the fact the code is for the front axle actuator but cutting off the plug and splicing on another fixed it real good.