This is my son's car and he had the oil changed the day before this started (doubt if it is related but you never know) He started it up to go to work and could not get it out of park and could not get the key out of the ignition. We finally got it out of park (after it sat overnight) and took it to a mechanic who has tried to diagnose the problem. None of the interior lights or dash board work but the brakes lights work. The anti theft service notice is on as is the TC warning light. The mechanic (not a dealer mechanic) indicated that he followed all the manufactures specifications but that information he has on that model and the way the car is actually wired do not match up. He said that there are no wires where there should be wires etc.. so he is not able to fix the problem. He said that he has seen a couple of cars, one an older Cadillac that have had the same problem that he could not fix. I am wondering if any other Cadillac owners have experienced any thing like this and determined the cause.