When i put my 106 in reverse the light will not come on

Reverse switch bad located in the gear selector

Not sure which part you mean no power.

For the New Body style 2004 ( not a Heritage or Lightning model )

If both Stop / Turn pins & the parking lamps, might want to check the ground pin to make sure it is good ( or what you are using for ground on the test light / meter ).

The trailer tow parking lamp circuit is fuse #10 to the parking lamp relay

The stop / turn circuits also have fuses on each one, Fuse #36 & Fuse # 42 ( R & L ).

The 7 pin has fuses for the battery charge pin ( hot in run position ) and the reverse circuit ( hot in run & when in reverse ), Reverse is also fuse # 10 to the trailer tow reversing lamp relay & the battery charge pin is fuse # 106 to the trailer tow battery charge relay.

Could be all the fuses are blown, or what you are using for ground on the meter / test light is not a good ground.

REVERSE LIGHT PROBLEM COULD BE LOOSE WIRES OR FAULTY TRANSMISSION RANGE SENSOR.THE REAR CENTER BRAKE LIGHT COULD HAVE FAULTY BULB SOCKET OR GROUND WIRE AND THE CONTROL MODULE THAT CONTROLS IT CIRCUIT.

Trailer Tow reversing relay ( non serviceable ) and the Trailer tow parking lamp relay are both fed from Fuse #10 ( coil on reversing relay is fed from reverse lamps & coil on parking lamp relay is fed from the parking lamps ).

Trailer Tow battery charge relay is fed from Fuse #106 ( coil is fed by fuse #13, hot in start / run position from key ).

Right Stop / Turn is fed from Fuse #36 ( powered from MFS circuit for truck stop/turn )
Left Stop / Turn is fed from Fuse #42 ( powered from MFS circuit for truck stop/turn )

Parking lamp is

Hi, If you solve engine idle speed fault this will stop warning lights.
Oil preasure falls when engine not at norm rpm because oil pump is not turning fast enough.
Put car on diagnostics to check for any fault codes

There is a fuse for the reverse lights. If you find that the fuse is good, have the reverse light switch checked, it's usually on the side of the transmission.

Assuming that the polarity wasn't reversed during the reinstallation, I would check the terminal ends of the battery cables.
One (+) is likely connected to a starter terminal, the other (-) either to the engine block or chassis sheet metal. The latter cable may be fastened to sheet metal and have an additional cable tying the chassis and engine block together.  
You should also have a multimeter so you can track down any breaks in the cables and to verify the fuses since these can have broken elements that might not be clearly visible.

check the fuses by the battery ,the big ones,then the other fuses ,if this fails then don mini and heels and drive to garage

i hope it fixed your problem can u please leave a rating

check the plug-in on the brake switch. also that switch is adjustable, maybe you can adjust it.