I parked my gx for roughly 3 weeks. Went to start it and it wouldn't start. Dead battery. I jumped it and drove it home. I had the battery tested and the battery tested fine. I threw my charger on it and let it charge. Drove it for about week. Parked it for 2 weeks for vacation. I tried to start it and it started fine. I threw the charger on it to see where the battery was. The battery was at 30%. My buddy had a similar issue with his Avalon and it was the alternator. He had the alternator tested and it tested fine, but he changed it anyways. It fixed the issue. Would this be an alternator issue? Im hoping so, I really don't want to deal with a bad ground.