Why wont it shift into reverse. After change code P2106 came up.

We just bought a beautiful 2004 Ford Explorer, with the center drop down dvd system for the back seat. The system turns on, loads the dvd, and plays, but has absolutely no sound. The only buttons on the dvd player/screen are play, stop, eject, and power. I got a remote and turned the volume all the way up but it's not coming out of any of the speakers, and when I push aux on the stereo system up front, it says "No Aux Device." The car didn't come with any headphones, is that the only way to hear the sound? Or has someone tampered with the stereo system and didn't plug all the wires in correctly? I'm not a car person, I just want my daughter to be able to use the system on long trips!

Putting the key in second position most lights come on, then in third position it gets a fast clicking noise and all the dials on the instrument panel go further down then they normally are and are fluttering very slightly in place at the same speed. ABS, check gage, check door ajar, seatbelt light, battery, service engine soon light stay on. Tried two keys, both do the same thing and also getting a low voltage reading. I haven't got a code, would this be a good time to go buy an OBD II? I have the manual, I'm reading everything front to back now to see if I can find out anything. Thanks so much in advance.

The gauge that tells you how fast you are going stops working?

can you help

I had recently gotten my fuel pump replaced not even a week after it was fixed I was driving and it just shut off on me while driving. I replaced the crankshaft sensor and still nothing I don't know what could be wrong I have had it little over a year when i try to crank it the truck makes a funny sound

What is wrong when my car is knocking when you crank it up

As of now i have no AC or Heat. The arrows you push to adjust temp or select setting light up with lights on but nothing else. Doesnt show temp either..Nothing..Read a few other places where people said its a relay and to turn key all the way back a few times and it will work. didnt work.(no surprise) after being off for a month or so my wife had to disconnect the battery and once she did IT WORKED. Tried doing it again and noting. Ive checked both fuse boxes. The booklet on the fuse box wasnt very detailed as to which fuse it could be so maybe i missed it? checked the relay fuse..blower motor and much more..please help!!

Vehicle was running perfect at 55 miles an hour and just turned off like somebody turned off the switch

interior lamp fuse location on diagram. fuse panel diagram in handbook does not show.

I have no power on any Windows but the sunroof works.

Can anyone give me an idea on what may be wrong?