I have a 2018 RX450h that I purchased in Jan 2019. I also just experienced a dead battery in what is essentially a brand new car. It isn't a cold climate thing as I live in Texas. I had not driven the car in about 4 days. At the dealership, I got the exact same explanation, either drive the car more or hook it up to an external charging system. Really??? You pay $$$$$ much money for a Lexus and this is the only solution they can provide. I appreciate this forum. After reading Zmanou812's post about the cigarette lighter adapter drawing amps even if it's not connected to a device. I checked and I had an adapter attached to the cigarette lighter. I've removed it and hopefully, this will address the issue. Thanks!!
