I have a 2006 hemi mega cab. A couple years ago started having trouble with the 4 WD engaging by itself. Got to the point was trying to put itself in four low on the highway. Also had no trailer lights from hookups on rear of truck. All research I did pointed to tipm so changed out and had dealer flash. This fixed trailer lights but not four wheel drive. I usually leave motor on transfer case unplugged so it cannot try to put itself in at a bad time. When I do have it hooked up you can occasionally hear clicking of the motor try in to engage. I'm at a loss any suggestions would be appreciated.

 

Never had this with a dodge but my wife used to have an F150. Her 4wd acted up. I replaced the relays for the 4wd (there were two on her truck) and it solved the problem.

I asked the guys at three different parts stores and was told that the relays could not be checked, however, I have an electrician friend who later told me they could. Anyways maybe a new relay would solve your issue.