I have a 2004 Deville 4.6 Base model. Battery not charging is not displayed. Yet I have to charger the battery with a charger everytime I drive it. I took the negative cable off the battery with the car running and it continues to run which makes me question wether there is an alternator problem. My car battery can't stay hooked up because the dash lights won't go off. The dash reads Service Security System. Now my question is, why is my batteries and I've tried two of them not charging? My volt meter says they are both at 12.66 volts. Why won't PRNDL go off the dash? And if the alternator is working why is the battery not charging? Is it because the security system needs servicing because even though I have to unhook the battery everytime I drive it it stayed up all Summer like that. Why won't it charge a battery now? I know I should have my alternator tested but I really don't think thats the problem.