I had the same problem with a Honda CRV i bought. Even though you turn the car off, there are still things that use electric. So, when I had to let it sit for a couple of weeks, I just put a battery tender on it and no, you don't have to disconnect the battery. I never had a problem after that.

 

There must be a lot of electronic systems running, which I understand given the computer complexities. I will just have to do as you suggest, which is to put on a tender during that period of time. Small price to pay for such a beautiful vehicle.

 

SOC will vary due to temperature and the capacity of the battery's health. The more you use it, the SOC % will go down over time. For my rule of thumb, if the SOC % goes down into the 60's range, I am replacing it.

 

This got me wondering about the battery in our 2016 RX350. The records on MyLexus show a previous owner (we are owner #3) had the battery replaced in April 2019. I got the battery and alternator tested at a local car parts place and it tested good. Apparently, the Lexus battery has an 84 month warranty. I didn't even know such batteries existed. I plan to test it again if we ever get a really cold day here in NJ ever again.

 

Well I waited too long! Sunday came out of a restaurant it was 5 degrees out, pushed the ignition button and got nothing. Fortunately a guy saw my hood up and had a portable jump starter. Thing was smaller than a laptop. Car started right away. I asked him if he knew where I could replace the battery on a Sunday. He said Auto Zone. Found the nearest one and they installed it. I asked him if they hook up power to the car while doing the replacement he said no. The battery was disconnected for about a half hour. He replaced it and the car started. i go to pull out and my big screen was dark. I turn around to go inside and the screen came back. Didn't lose my radio stations and my phone connected to the car. Not sure if I should have things checked out at the dealer.

 

I read that when changing a battery, a second one should be connected so you don’t lose all the previous factory connections and settings. Given that info, I would only have a dealer change the battery (unlike the “old days”). I would recommend you have your dealer check things out just to be safe. The electronics are finicky. Hope that helps.

 

You can always do that but in my experience it was not necessary.
I changed mine (see post #181 above) and had no problem with any electronics. No memory items needed reset.
Viktor video shows the same and he even indicates that at the shop (his previous dealership gig), they never use a back up. Just remove and replace. Just my experience.

 

Hi. OK. Good to know. Thanks.

 

I changed my battery 4 years ago. Have the new one close at hand. Take the old one out and put the new one in. Hook up the cables and you are in business. Not rocket science. Don't monkey around and just get it done. You should have no problems.

 

Just remember not to have the new battery in the cargo area with the hatch closed before you remove the old battery.

 

Just a recommend on batteries. Costco batteries are no longer 3-year replacement, but 3 years pro-rated. Probably from all the customers returning batteries around the 3 year mark for an exchange. However, Walmart higher end batteries offer a 3 (some 4) year replacement. The price is not all that much more than Costco.

 

Thanks for sharing. Good info.

 

"Parking Support Unavailable" error will disappear automatically when you drive your car for a minute.

 

The battery for your car is very important. You will need a new one every 4 - 5 years at least. Do your research.