2023NX350h

I had something like this happen. I was cleaning my 2023 350h in the garage and had the music playing (engine off). About 15mins later the car died....only headlights were working. Couldn't start car with the key held up against push button start. I tried jumping it with those portable battery pack things but it didn't work - tried battery in the front and back. Called Lexus roadside and they sent a tow truck. He used one of those high power battery pack things to jump start the car for me.

Lexicon1

Now youve got me concerned about being in the same position.
I have a battery jumper pack which has started a Lexus SC430 V8 engine , why would a battery pack which only needs to power a computer not have enough juice to do that?
Was your car in ACC mode when the battery eventually went dead ?

2023NX350h

No idea....2 different people mentioned it takes more power tp jump these types of cars? One was the tow truck driver. I'm still using the old battery jumper pack that has the heavy batteries - lead acid? The tow truck driver had the new lithium ion Noco type.
Yes. I had it in ACC mode and was running the music.

Lexicon1

Thanks for the update 2023NX guy,
The jump start battery I have is also a Lithium based battery jumper type.
Looks like its time for me to get a second one for the NX also.
ACC mode.... tough lesson, will make sure I avoid it
Thanks

Susido

And if those don't do the job, you get to crawl though the back and undo the hidden panel and release the latch from the inside. That's what I had to do when the 12v battery completely died overnight for no discernible reason. Trying to charge the battery from under the hood or jump-starting it was completely hopeless as the 12v battery was that dead. This occurred during some very cold weather exactly 1 year ago. Fun Xmas that one was.

Lexicon1

A2023LC500
what was the verdict on your dead battery issue? You mentioned you would let us know what the issue ended up being.

RandallC

Verdict: The dealer claimed there was nothing wrong, nothing defective, no reasons why (except that it was somehow our negligence), etc. Annoying, but based on the responses here on Club Lexus, it is clear to me that there is a fundamental flaw in the architecture of the entire system. At least there should be a warning - there are warnings for everything else. At best, when the car is in ACC mode, the 12V system should somehow be able to "draw" from the Traction Battery.
- Randall

SgtLip

That was exactly what I had to do when I got my windows tinted. I had to crawl through to hook up the charger.

I sold my NX450H+ yesterday. No more problem. Took a $30K hit on the cost though.

Lexicon1

[QUOTE=SgtLip;11643030]That was exactly what I had to do when I got my windows tinted. I had to crawl through to hook up the charger.

I sold my NX450H+ yesterday. No more problem. Took a $30K hit on the cost though.[/QTE]
Do you know if when they were doing the window tint that they had it in ACC mode? Likely?
Am having PPF in a few weeks, I will be leaving a large note on the vehicle so that they only leave it in READY mode if needed.
Hard to imagine you could not jump start the system via the hood charging port and had to crawl back to car rear battery.
Maybe I also need to bring my battery charger to the PPF installer just in case.....

SgtLip

[QUOTE=Lexicon1;11643039]They had the large commercial charger and we attached to the bolts under the hood and let it set awhile. Nothing. Would not turn at all.
That was when I had to jump into the rear and hook it up. It sat for 5 minutes and jumped right over.

No idea what mode it was in. The key was laying in the wiper well. All doors were open as they were tinting all windows.

Remind them to NOT use a steel razor blade on the door windows. You and them will regret it if you do.

lsft

Unfortunately, it's a safety feature. When in ACC mode, they disconnect the traction battery from the system so that there is no flow between the systems. The only time it's connected is when the car is running or charging. This is a problem with many BEVs, PHEVs on the market. Tesla would wake up the car and use the traction battery to charge up the 12V. I hope one day Lexus would push an update to allow something similar to happen.

ptung07

I fell victim to this issue on my 2022 NX 450h+. Awaiting Lexus Roadside.

egandt

Just happened, I normally drive on battery (why I bought a hybrid), my normal daily trips are under 10 miles, over the last 2 weeks I went about 15 all on battery this morning DOA, seriously no warning nothing. Just a message unable to release parking break and that is it. Had to crawl into the back to check the battery was 0% charged and 5 volts (not even 12 output). Now this is a Hybrid, I replaced an outback as it ate a battery every 10 to 11 months, would have assumed a Lexus would be ok. Seriously why even have a 12V when I have 14KW! Normally I do about 60 miles a week, and of that only 5 to 10 is on the Engine, but none of that explains no warnings.

NX450Guy

We-of-The-Low-Mileage-NXhybrid-Club feel your pain! My NX450 died twice in the first 300 miles of ownership. According to a friend, Lexus corporate can only advise us to complain to Brand Engagement at lexus.com by clicking on “support.” Or call (800) 255-3987. Lexus needs more complaints to make sure they push through fixes besides changing our lifestyles or trickle chargers. I was told the 12 volt they offer us is the only option for the NX, any attempt to put in a bigger battery will void the warranty if some electrical issue arises afterwards. Really crazy this defect hasn’t been addressed yet.

Susido

With it warming up significantly, I finally swapped my completely dead Lexus 12v battery for an AGM battery sold by Costco (the only compatible battery they sell apparently). Same physical size, quite a bit more CCA. The original isn't AGM is it? Vehicle (350h) starts and runs OK now other than the engine light being on and the see dealer message constantly appearing. I understand the new battery will require some dealer programming to reset something or other. It's been a huge PITA, the second straight winter with the 12V battery failing completely and suddenly in cold temperatures. If I could afford to do so, we would be owning a different vehicle by the time next winter rolls around.