Power window switches fail from water dripping on them when the windows are left open are expensive to repair. The vacuum heater/ air conditioning controls fail to operate correctly- the vacuum lines are hard to find and repair. I was told it might cost $1000 to repair. The vehicle is a 2003 Chevy Blazer, I am a mechanic and I can not find where the vacuum lines are routed.

- Willmar, MN, USA

My 11-month old 2003 Chevrolet Trailblazer has had multiple quality problems, twice affecting my safety. Most of the problems have been electrical in nature. The 4WD has become inoperable numerous times, once while driving in snow. In another incident during a severe thunderstorm at night the air conditioner (A/C) failed and I was unable to defrost my windshield in order to see. After one dealer failed to diagnose the 4WD problem, another dealer replaced my ignition switch because the technician said I had no power at all going to the "rear grid." I continue to have intermittent electrical problems, including near stalling at a traffic light, and ongoing 4WD failures. The car also has very jerky motion when in 4WD reverse, of course, when the 4WD is working at all. The dealer told me that was normal and now I see there is a service bulletin on the problem.

- Arnold, MD, USA