A-The infra red key will activate the doors with the red blinking light and the green blinking light, however it will not open or lock the vehicle and when pressing the infra red button you can hear sound out of the trunk. what causes that and what part do I need.

B-After taking the car in to repair the Ac for over $3000 it developed a new problem that the dealer suggest it is not their fault? Now I have air coming out of the sides only and not from the center.what causes that and what part do I need.

Any help would be much appreciated I am giving up on the Benz dealers in Kansas City.. I have had too many bad encounters.