I have seen numerous posts concerning 2004 and 2005 Cts no start issues. The symptoms include turn the key and nothing happens, key stuck in ignition switch, gear indicator light out, and all other dash lights working. I have pulled my hair out trying to find a solution without sucess. that is util I came across a old recall concerning all 2004 and some 2005 models having to do with a ecm reprogram. the recall number is 05524. After contacting a local Cadillac dealer they searched their database and found that this recall repair was never done on my vehicle. The database showed that the recall was closed but refereed to no mileage or time limit. After contacting the GM rep, they called me and told me that GM would still honor the recall.
The old ecm would not accept the new programming so the ecm was replaced. Problem solved. Oh yeah,
NO CHARGE!! I couldn't believe it!!!