Cruise Control problems of the 2008 Buick Lucerne

My father-in-law had the complaint that his cruise control was not working. I checked the car over and it was working fine. On his way home it quit working after about 75 miles. Another check and all was fine. Shortly after that, I just happened to be following him and the brake lights came on and never went off. I confirmed with him that his foot was not on the pedal. I put together that the brake lights were coming on and shutting off the cruise control. He took the car in and they added brake fluid. The cruise control kept kicking out. I came to the conclusion that the brake light switch was either out of adjustment or defective and wrote it down for his dealer. It turned out the switch was defective and it was replaced. The car has 68,000 and garaged. As a driver you won't know the brake lights are on without looking or find that the cruise control was not working. With the brake lights permanently on, other drivers can't tell when you are actually slowing down or stopping, and that is a potential risk for being rear ended. My father-in-law tried to be aware of this situation by engaging the cruise control when possible. As long as it was working, he knew his brake lights were operating as they were suppose to. Happened on highway and city, moving. Brake lights remained on after stopping. Everything was back to normal after awhile, I suspect inside temperature was at play somewhat also.

Buick Lucerne electrical problems - onstar suspected. I 'm not sure that this is or isn't a safety problem, but after complaining to Buick I was advised by them to file a claim(?) with you. About a month to 6 weeks after an in-town accident (10/22/16) that was repaired immaculately by the local gm dealer, the car sat in a park and fly lot for about 5 days while we had gone visiting out east. When we got back the car was dead as a stone. After a triple a call we got home and immediately got a new battery (12/20/16), even though I was surprised that it had gone dead because there was no warning (slow starting, etc). However, in the next 6 months or so, two more new ones went dead (2nd 1/3/17, 3rd 3/13/17) and were replace by the dealer at no charge. However, in the next year or so, not only did the onstar go dead, the brakes lights quit and was replaced, the cruise control quit, the stabiltrak quit, (and both were replaced). My insurance company - american family - informed me that the accident is not the cause of the problems. So finally I took it to another shop cas (complete auto service - austin) that does the city's police cars, and they ran a diagnostic on it and even though the onstar has quit working, by removing the fuse in it that 'seems' - after spending over $1300 and still not replacing the onstar for another $650, - to have solved the problem. At least so far.

The contact owns a 2008 Buick Lucerne. While driving approximately 55 mph, the cruise control failed. The vehicle was taken to the dealer for diagnostic testing and was repaired, but the failure recurred. The contact was unaware of the specific repairs to the vehicle. The manufacturer was not notified. The failure mileage was 50,000.