Tank Assembly problems of the 1998 Mercedes Benz SLK230

My seat sensor in my car failed at 7000 miles of use. I have a low mileage mercedes and it will cost almost 875 dollars to replace. This sensor disables the passenger air bag in case of a baby seat. I have never used a baby seat in my car and it is now in the locked (off) position making the car extremely dangerous for the passenger. Fortunately I rarely have a passenger but I want someone to investiaget how often this sensor fails. When the car was new it was touted as a super safe car in case you have a baby. Now that it is in locked off position it is a super unsafe care for an adult. Philip chao VIN wdbkk47f3wf060735 by the way there are also other defects in this particular car. The air compressor exploded at about 4k miles. That was replaced by the dealer at his cost. The battery died at leass than 3 years but I had it replaced by the dealer at 4 years also. And. . . Now they say there is a possible problem with my fuel tank versus a malfunctioning valve. This is a lot of problems for a 7347 mileage car.