I have a 2000 Monte Carlo SS with 54,000 miles that is currently at the dealer with similar problems. They have had it for a total of 7 days over the last 2 months. It started with 3 warning lights coming on at different times, but progressively got to the point last week where 5 warning lights would come on for 5 seconds whenever the turn signal was used. Also, it started having unpredictable starting problems. Previously, the diagnostic test couldn't find a problem and the dealer said they couldn't do anything. This time the diagnostics showed over 20 error messages. The dealer says that their GM database says that replacing the ignition switch has solved the problem on some occasions. I hope so since I just authorized the repairs and am fed up with the problem and GM's crappy service and attitude.