Pontiac Repair: 2008 Pontiac G6 3.5L V6 Wont Start, pontiac g6, radio thing

Question
I was driving my car and it stalled while driving.  After pulling over, it started again, but when I then made a stop at a local store and came back out, it wouldn't start at all, and the odometer says "error" on it.  My local dealer is of course quoting the GM playbook and trying to tell me that my aftermarket sound system is to blame and that my warranty may be voided, even though the install did not involve ANY splicing into the factory wiring.  Do you have any suggestions on where to gently point them to?

Answer
Hi Peter:

well it can be just about anthing. Yes it can be the radio doubtful but you never know. GM's stand on any electrical issue now is to remve or disconnect any and al aftermarket accessories on a car FIRST before any reair attempt is made. Yes I know it more than lilley is not the issue but there have been so many cases where after market stuff is added to cars and it cause all kinds of wierd issues they want that varaible of a problem taken care of first. Now back to your issue. My guess is that one of the modules in the car has gone bad and that is causing an communication problem between them. all the modules are tied together on this car and iff the communication between them is lost due to one going bad you wil have the "error" on the odometer because it's not receiveing the messages it needs for the other modules. It's going to be a process of elimination to see which one is the culprit on this one. BAck to the radio thing you never know it could have been spliced into a ground or power that is used by one of the cars's modules and is causing this issue. Doubtful but you never know. Good luck and let me know what they found.