I have these tail lights on my 04 FX4:

http://www.ebay.com/itm/04-08-FORD-F-150-F150-STYLESIDE-LED-TAIL-LIGHT-BLACK-05-06-07-FX4-LARIAT-2DR-4DR-/370795519023?pt=Motors_Car_Truck_Parts_Accessories&fits=Year%3A2004%7CModel%3AF-150&hash=item5655229c2f&vxp=mtr
I just recently noticed after coming back from some dirt roads in the woods that my left turn signal was clicking and blinking really fast. My tail light does light up when my lights are on but just no turn signal and I think the brake doesn't work either.

 

You may have jostled the solder loose on one of the resistors. You get what you pay for.

 

The tail light turns on when I turn my lights on but the turn signal doesn't work

 

I have the same kind of lights in black. After 3 years I have 2 banks of 3leds out on each one. Only the passenger one hyperflashes. I'm gong to open them up and see whats wrong eventually.

 

They are put in groups of three to a resistor, so obviously a cold solder joint on said resistor. Again, YGWYPF

 

So I should be able to open them up and just resolder those sections, right?

 

I'm 90% sure they are covered in potting material, so no.