I had my battery replaced twice by the dealership after it died multiple times (as I noted in your other thread). never did I lose any presets when the battery died or was replaced.

I do know however that removing the battery or having it die with result in the system completely reloading not just rebooting, the whole computer system.

in one case for me, I removed the battery and placed it on a charger for several hours, when I put it back the system reloaded but the car had a horribly rough idle and would not shift out of 2nd gear. I disconnected the battery for several minutes and reconnected forcing another system load and the issues went away.

Dealership told me they use one of these when they change out batteries to prevent that issue:

https://www.amazon.com/Battery-Tender-081-0154-DL-Connector-Maintainers/dp/B007KJ2RZK/ref=sr_1_3?ie=UTF8&qid=1543515172&sr=8-3&keywords=battery+tender+obd


I bought one, works on any car with an ODBII port.

 

The only loss I have witnessed after replacing my battery at the dealer was I lost my saved g-force records. My seat presets and the data stored in my nav system were still there. I don't know if they used a tender or not. My old battery had a bad cell and wouldn't hold a charge anymore. But it still had enough power to turn on the dash lights. So it never completely died.

 

I put an Optima in mine in my garage. The Optima's don't fit so I had to make a custom spacer. Worked fine zero issues. I can't remember if anything had to be reset.

 

 

Hi-
I'm new to the forum and couldn't see any replies to your question about DIY replacement of the RC-350F battery. I'm trying to do that task now, and cant figure out how to get the plastic battery cage out. It's most certainly NOT a case of disconnecting the cables and lifting it out!
Can you help?
Thanks, Bruce

 

RC350/300/200t forum would be the right place for your question..

 

Just replaced my battery today. It was a little PITA to figure out since I thought it was simply unscrewing few bolts and lifting out.
You need press those tabs to loosen two metal brackets attached to the plastic cage. Secure, but totally unnecessary imo.

 

When I installed my AntiGravity lightweight battery, the only thing that was frustrating was opening one of the two plastic tabs. One opened rather easily, but the one on the side got damaged in the process while trying to free up the cage. Otherwise, the installation was super easy and quick.

 

I reset my car by unplugging the battery after I installed my Invidia exhaust and I didn't lose any presets (radio, seats, etc)
I used one of those devices that I plugged into my cigarette lighter when I cleaned my terminals and it did not save anything more than just unplugging the battery completely. Probably a waste of $ to buy or use one of those.

 

If you have one of those portable jump starters ( there are cheaper ones than this... ) you can just attach the jump start cables to the car terminals before removing those from the battery you are replacing. That saved everything on my Lexus es350. I wish there were more options for Li Ion battery replacements. I did that replacement on my BMW motorcycle (generic) and no longer have to use a trickle charger through the winter and its lasted 5 years longer than the OEM piece of trash--yah, I had to modify the place where it is stored on the bike since it is SO much smaller and lighter. After my RCF is out of warranty I will probably do something similar since I don't expect to drive this car very much in the winter.

 

My 2015 GS350 radio and SD card also broke when my battery died. When trying to start the car with the dead battery, the whole car and infotainment system hysterically flickers. After going to the dealer, will cost about $3500 to replace the radio. This is absurd that this is happening! Have been a lifelong Toyota/Lexus owner and am so disappointed that this is happening for such a common scenario. I'm so scared that the radio will break again when the battery dies again in a few years. So frustrating. Can I get a show of hands this is happening to? Wondering if we can collectively band together and get Lexus to fix this defect.

 

This is the current battery that I have that is not holding a full charge. The last test was 11.7 and it's 3 1/2 years old.
Also, maybe a higher minute reserve capacity would be a battery I should look for.

 

I don't even use the radio and the cd player doesn't play. sigh
I'll be grateful to have it drive again without the VSC lights coming on and not allowing the car to start
again until I get out and disconnect the battery to clear the light.