Diagnostic fee charged, and was told I needed a new battery, that it had a dead cell. This was not true and took the car for a second opinion. The battery was fine, and I still don't know why the car locked up and would not start one evening. It was towed by Onstar to the garage, and they worked on it without my authorization the next day. They want a diagnostic fee for something that is not even an accurate estimate of the problem. There are electrical problems in the computer of this new 2006 GMC Envoy, and they did not diagnose that. The report was untruthful and fraudulent.