Same with any hybrid yo pretty much do gown hill for very long breaking down,

 

I have a related question. How much variation in charge level are other LS600 ownere experiencing while driving? My 2008 seems to very quickly go from fully charged (one bar short of the top), to fairly discharged (only a couple of bars showing). This may be normal, as the batteries are used to switch to pure battery mode while driving slowly or to augment accelleration at times. I'm just aware that my batteries are 6 years old and, while no one has reported battery failure on a 600 yet, I want to make sure to report any problems before the 8 year warranty is up. My thought is that if some of the individual cells failed, the car would exhibit this sort of behavior (quickly discharging).

So does your battery level roam from high to low and back again frequently while driving in town?

 

Mine goes from almost full to purple fairly quickly, especially right now when I am running the AC, seat coolers (2-3), radio, 6 yr old watching a DVD in the back seat, DRL's. Everything you have turned in will drain that battery.

However, it will charge pretty quickly once you drive and/or coast down a long hill.

I think what you are seeing is somewhat normal. Someone correct me if I'm wrong.

 

When I was in for service the Lexus Techs mentioned it was normal. I also asked them if it is normal for the hybrids to need a jump while doing alignments, they said it does happen often..and not just hybrids. I also asked if it was normal for the traction (hybrid battery) to get low enough during an automated car wash with the car on and in neutral.. They said yes as well. The hybrid system does not charge while the car is in neutral. So if you are going through a long car wash and your charge level is already low at two or three bars and you have the AC, NAV and Radio on..if your headlights are on whether DRL or in AutoMode..it will discharge even faster.

 

Post is several years old at this point. Today is 31 August ’24. Just confirming most of what I’m hearing above in earlier comments, for clarification (to relieve others experiencing the same thoughts): my ‘08 LS600hL (170kmi with NO hybrid battery replacement yet to date) will also not hold hybrid charge when undriven for several days, but will charge within a mile or 2. BUT, will also discharge incredibly fast even after a long highway drive (& the patented one bar short of full battery) charge drops to one or 2 pink bars after driving into stop/go traffic, or a couple of “Pwr” blasts from red lights will drain it fast…
But, yesterday I drove it 200mi highway 5000’ to 7000’ elevation and it STILL got 27mpg averaging 75-80mph. Which is still very impressive, imo.
Now, my AGM-type starter battery (in the left side of the trunk) will absolutely die if car isn’t driven within a couple weeks bc it still runs the security system n sensors n whatnot. I keep my starter batt on a trickle charger when I don’t drive it for more than a week. Dang oem starter batts are ~$4-500 so trickle it!

After this pic was taken (showing 24.3 mpg) it climbed to 27mpg on the highway traveling above 70mph. I believe most newer hybrids get better mpg in town — not my LS600h. It loves the freeway

 

Sort of related, also relatively new owner of a 2009 600. I had read that Lexus can test the battery for its health during routine maintenance. Is this true? Has anyone had that? And did Lexus charge $$$.

Thanks in advance!

 

I'll answer my own question - YES! Lexus can and did for me as part of my service appointment. See attached photo.

Lexus tech battery test