IlanFriedman

I've read (nearly) every post in this thread, are we any closer to discovering exactly what the issue is? I'm dying of suspense.

Hues10

Unfortunately no. I bought a scanner to read the codes, however the scanner apparently did not scan Hybrid system codes, only normal check engine stuff I believe. In the meantime I had charged up my 12V battery to make sure it was fully charged just in case. The only other thing I did on the purchased scanner was hit the clear error codes (even though it had not scanned any), I decided to then start the car, and like magic, as soon as I started moving forward, the error message was gone and the Battery graphics were working again. So I never brought it to Lexus, figuring if it happens again, I get it towed to them 45 miles away. Have been driving it on my normal 10 mile round trips, and keeping the battery charged every once in a while. It did do a 45 mile round trip with multiple stops yesterday, no issues. The BCLexus battery monitor is already ordered from Amazon. The only theory I have is that my 12V battery level was low, even though the car started and drove about a mile before the error message first appeared. Nobody else with this generation has said boo about this error message appearing on their vehicle. The car drives normal. It is the strangest thing. If it happens again, I will update.

IlanFriedman

I'm new to the whole hybrid scene, I joined the forum bc I'm interested in a 2015 GS450H and there are essentially only 2 things holding me back.
1. There is so little information out there about this model
2. Buying a newly 10 year old luxury hybrid scares the living daylights out of me, I don't know if I can afford replacing the battery in another few years.

I also don't know much about hybrids, like what is the 12v battery, what's the traction battery, how do you charge your 12v or keep it on a tender. This forum has been fantastic so far but I'm still learning

spineman

Well, I'm glad the error message has never happened to me, but I will let you know if it does. Having a low 12V battery is my issue, but it seems from other forums (NX hybrids) that they have very similar issues with the low12v battery. I'm going to hard mount the terminals now to the battery for my tender. Just going to be preventative maintenance from now on.

@IlanFriedman 1. All the information is right here on this forum that you will ever need.
2. I wouldn't be scared. The batteries for the Toyota Hybrids are a fraction of the cost of say a Tesla battery. Depends on the cost of the car, miles, etc. I bought my 2013 3 years ago with 82000 I think. It now has over 130k and no issues with the traction battery (moves the Car) just the 12v battery which just turns on the electronics of the car. And that is just recent.

spineman

You can get that same exact device for $10 on Aliexpress. After hearing about that radio issue, I'm not going to use my mute button anymore! But, I need to at moment because someone pushed in my volume **** again

bclexus

@IlanFriedman - I don't think buying a 10 year old GS450h should scare you. Maybe you aren't aware that the Lexus warranty covers the hybrid traction battery and hybrid related components for 8 years or 100,000 miles. And, beginning in 2020 Lexus has increased the warranty coverage to 10 years and 150,000 miles. Clearly, Toyota/Lexus is very confident in their hybrid batteries and components - and that goes for pre-2020 hybrids like the 2015 GS 450h you're interested in as well.

► Starting with the 2020 model year every Toyota hybrid battery warranty increased from 8 years or 100,000 miles to 10 years from date of first use, or 150,000 miles, whichever comes first.

"This enhancement serves as an indication of our confidence in the quality, dependability, and reliability of our products."


This change in Toyota's hybrid battery warranty starting with the 2020 model year vehicles signifies strong confidence. While it doesn't pertain to pre-2020 model year hybrid batteries it certainly provides an added degree of assurance that Toyota's hybrid batteries are long-lasting and very reliable.

I find this also very interesting: The hybrid battery may be eligible for warranty replacement if it is found to have less than 70 percent of its original charge capacity within the warranty period.


This hybrid battery replacement eligibility proclamation brings about the question of - under what conditions a customer's hybrid battery is or can be tested to determine if it has 'less than 70 percent of its original charge capacity within the warranty period', and what exactly this diagnosis/testing and replacement process actually entails. I trust this replacement obligation applies to all Toyota hybrid batteries that are still within its warranty period.

bclexus

@IlanFriedman - I suspect this 10-year-old 2015 GS 450h you're interested in will be the most impressive vehicle you've ever had - and will only be surpassed by another Toyota/Lexus hybrid you might acquire in the future...

The GS 450h's 12 volt battery does not crank the engine like with a typical non-hybrid vehicle. With the GS 450h, the ICE (internal combustion engine) is actually started (i.e. cranked up) with power from the traction battery. The car is designed for the traction battery to always retain plenty enough power to start the ICE and this is actually accomplished by using one of the GS 450h's two motor-generators (a.k.a. MG-1 & MG-2); more specifically the ICE is started by MG1 (see image below).

The 12 volt battery's primary purpose in the GS 450h is to power the vehicle's accessories. The 12 volt battery is kept efficiently charged by simply driving the car. The GS 450h has an AC/DC converter that performs this task without any rotating mechanical device like a typical pulley-driven alternator that is needed in a typical vehicle with an ICE.

The Lexus GS 450h is a fantastic automobile with a wonderfully designed hybrid powertrain [that I like to say] is how I think NASA would have design it. And that goes equally for the amazing eCVT transmission (image below) that is so delightfully buttery smooth - like no other transmission you've ever experienced...

Lwerewolf

There's literally so much information out there about this particular model. It's essentially a 3GS with a better (well, more efficient) engine and inverter (unbreakable), better battery layout for boot space (not sure about servicing), I think the same battery modules as the 3GS (and respectively all the ni-mh priuses).

Look up what a new or refurb battery'd cost you, check if you're still eligible for hybrid warranty and decide. Rest of the costs - see the 4GS in general, a lot of things are the same. Look at this car like a GS350 with a slightly different engine, completely different (and almost as close to bulletproof as possible) transmission, a hybrid battery to potentially worry about and a brake-by-wire system (it's a hybrid). Hybrid-wise, it's pretty much a RWD prius.

You don't tender the 12v, you replace it when it's gone (usually no signs since it barely gets used) and move on. You check the hybrid battery with dr. prius or with techstream or whatever - let it sit in neutral with all accessories on full blast (AC, heated seats, etc - wouldn't bother with the stereo) until the SoC gets to around 40%ish - then look for the biggest difference between two battery blocks (block = 2 modules in series, block = 6 prismatic 6.5ah ni-mh cells in series, you can't get individual cells). If you ever get 1.2v or more (nominal voltage of a ni-mh cell - i.e. probably a cell is busted) - car sets the p0a80 code. New ones tend to have a max difference of 0.20v - it's what mine (3rd gen GSh) gets with modules taken out of salvaged C-HRs back in 2018, so 170,000km (~100k miles) later - and I've never cleaned the hybrid fan. Again, that's a 3rd gen GS hybrid, they're "known" for chewing traction batteries and inverters. So yes, it can happen, and yes, you most definitely should be able to afford it if you're driving such a car, since driving a luxury vehicle and being stressed about it doesn't really strike me as anything close to a luxurious experience, but in this case, the hybrid isn't what I'd call more problematic than the non-hybrid (i.e. the GS350). Just make sure that you like the way it drives - realistically it's anything but sporty (still very capable, just muted), but it's a great daily, if the cargo space is enough for you. Theoretically the brake pump can fail, but let's say that it's an extremely rare event.