Hi, I just bought a brand new 2009 L570. The battery went dead the first week I got the car. It was replaced and then the second battery went dead. The dealer had it flat bedded into the dealership and did testing. They say I am not driving it enough. I use the car at least five times a week but Lexus is telling me that I am not driving it far enough for the alternator to charge the battery. Also, If I let the car sit for three days, the battery goes dead. The dealer has put on a plug in trickle charger for me to plug in my car every night but this sounds odd for a car that costs so much money to be 'plugged in'

Is anyone else having this problem? I checked the RX350 forum site and they are having problems with the batteries going dead also.

Ok so you drive it 5 days out of 7 days in a week? That is the way normal people drive. That is a ridiculous statement from the dealer that you are not driving your car enough. I can't believe they would even tell you that. There is no way the battery should be doing this x2. You should be able to leave any car not driven for weeks with no problems. When my room mate went to Mexico his LX sat in the garage for 1 month without being driven and started right up when he got back. Something is draining the battery when the car is off….as if something is staying on that should turn off. Or the alternator is bad. But is is also possible but rare that you get 2 bad batteries in a row but it can happen. The NEW Lexus battery I had in my LX lasted only 6 months. So instead of getting it towed an hour and a half away to my nearest Lexus dealer I went to autozone and got a Duralast and did it myself and haven't replaced it in 3 years.

Battery dead just for leaving the car sitting for 3 days? that's a silly statement. it shouldn't happen to any car. I too can't believe the dealer told you that. I recently have left my LX570 in airport long term parking couple times. The car was sitting in the parking lot for 5 days each time. My LX570 started right off both time.
Just thought about one question you should ask your dealer. Did they start your LX570 everyday and drive some distance before your purchase while it was sitting in the dealer's lot? I am sure the car had sitting in their lot for more than 3 days without moving an inch.
Can you read the posting "Annoying Noise From Brake Accumulator", see if your LX570 making the same noise?