Very common on the WJ to happen. These wires are too stiff and will break after so many times opening/closing the door. It happened on mine and i did a temporary repair (since 2 years ago) and i just soldered them together.
Ofcourse best would be to change the wire(s) for a more flexible one, but use the same thickness.
JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
Monroe Reflex shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.