i've seen detailed explanations about this in xoutpost. basically once the rubber at the end of the cable that drives the door lock deteriorate over time, moisture gets into the cable.
once moisture is inside the cable, if the temperature drops to sub zero levels like we have now, the moisture freezes inside the cable. effectively jamming the cable.
the remedy if i remember well, was to open up the door panel and replace the cable ends, or ensure that water doesn't get in their..
there's another known problem with x5 door handles - that you shouldn't force! the internal alloy metal frame onto which the external door handle is fixed onto, has 2 hinges which are rather flimsy. force them in this kind of weather and u can break the hinge. good news is that thats such a common fault that usually bmw has this part readily available in stock
- SO DON'T FORCE THAT EXTERNAL HANDLE!
if it was toyota they'd have recalled the whole lot and released a redesign on this door handle i think!
Current: BMW 640i Convertible (320PS)
Audi A7 Sportback 3.0 T FSI quattro (300 PS) SE STronic

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