My wife went to start with key and ... nothing.
I tried 5 mins later, started fine but now "SERVICE SECURITY SYSTEM " is on.
Any suggestions or know how to clear ?
Car starts fine ( 2007 SS) ,locks all function ?
Thanks,

 

Sounds like the ignition switch or the chip in the ignition lock cylinder is going out. It generally takes a 10 minute wait for that to reset, but you can only do that so many times before it goes out all together.
Also make sure the battery is holding good voltage. A low battery can cause this too.

 

I agree with plumbob on ign cylinder as suspect. These dam random electrical issues are a nightmare. Just last week my 06 SS out of the blue when started began reading service battery charging system On the display.
Immediately checked battery voltage, all good at12.8 v, then alternator showed 13.8.
Turn out there a technical bulliten to reprogram the bcm it's a common issue. Had it done no issue since. The normal diy person is caught by the short hairs on some of these gremlins.
Good news is only about 1 hrs labor was all charged