Haven't started in 2 days.

This morning it would not turn over at all. All accessories worked , but very weak. Tonight everything is dead!

Could it have drained so quickly?, It's 11 months old.

Should I replace the battery , or should I start troubleshooting?

Thanks in advance

Remove a battery cable and put an amp meter between the cable and the battery post. Normal drain on a 700 series should be about 2 - 2.5 milliamps from the radio and clock (make sure no lights are on, the doors and trunk are closed, etc.). Anything more than that and you probably have a short.

I'd charge the battery full, disconnect it from the car and put a meter on it, see how it drains as a stand-alone for a few days. I gotta tell you, I've been having bad luck with new batteries lately. cars, boats and motorcycles.

Assuming it wasn't almost dead from lack of charging when you last used it, trunk, hood, glove box and dome lights that didn't turn off properly top the list. Radio power amps area also known to cause (sometimes intermittant) battery drain.