I have read that the wires that run into the door might sometimes break. You might want to look in the rubber boot that goes from the fender into the door and see if any of the wires are pinched or worn
Yeh, thats unfortunately a weak point of the wiring. One of the wires in the drivers side door boot is broken. I had the same thing some months ago. The wires are quite thick and very stiff and will break after many times opening and closing the door. I did a temporary repair, but want to change the whole wire for a more flexible one when time allows (will probably take a loooooong time to do so)
At mine the black wire broke, but can happen with the other wires as well.
JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.