How do I reset the security system in a 2004 bmw car
do you mean the code function in the instrument cluster that locks out starting the car?
Last month i was facing the same problem. The alarm went off, i push the alarm reset button! after that the car went dead, will crank, will not start! Then i take my car to a certified European Auto Tech BMW center Their specialist with the use of correct computer re-set my car system.
Search BMW X5 Questions
BMW X5 Experts