today on this cold morning my range rover, would let me only unlock the driver side door but when i opened the door the alarm went off and the engine wouldn't start. after being fustrated for a hour going online reading about the lock system and calling the dealership which was no help they said just get it towed in. Anyways me being somewhat smart, thought about 2 things the only difference was it was very cold this morning, and the car didn't read the key. so i got a lighter heated up the key just a little placed it inside of the lock and bam all the doors unlocked and i drove off a very happy man, that was a hour and a half late for work :-) the end.