'07 DTS won't start
 

I am totally stumped. I put a new battery in my 2007 DTS and now it won't start. Battery is good. Key FOBS don't work, power windows do. Air cond and radio do work, power door locks don't. Will not even crank when key is turned. I thought it had to do with the security system but security light goes out immediately when ignition is turned on. Continuous scrolling of 'service suspension system' and 'service A/C system' on dash with key on. I swear, all I did was change the battery and now the car is haywire. Any thoughts? [I have done all the key in the door lock and key in the ignition tricks to have the car relearn the key] Any thoughts are appreciated.