Thanks for this thread and for everyone who participated. I've been lurking here for the past 2 months.
I bought a 2007 GS450h for a great deal but it came with hybrid battery issues.
I started by replacing 2 weak modules then cleaned all the copper bus bars and modules' 10mm nuts because they were extremely corroded. This thread has been a great help with that.
The car is drivable now but the Hybrid System Check comes back usually 30-60min of driving. I noticed that the failure comes faster on hot days. I once drove the car from Louisville to Chicago on a really cold day without issues (300miles mostly hwy miles).
Now I have a conclusion that it's a heat distribution issue. Battery gets hot quick and causes the failure. The blower gets loud when the battery is hot but it seems to be doing what it supposed to do.
It's worth mentioning that the battery has been previously worked on and there is a huge chance that some parts are missing. The previous person who tried to fix this lost plenty of nuts, screws, and one of the blower's air ducts which I replaced.
I noticed warm air leaking directly out of the bottom LH side of the battery. See picture.
My question is does it look like it's missing a part there where the red arrow is pointing. I reinstalled the duct multiple times but always ended up with a small gap. Is there another duct piece to fill that gap?
