vincej

So far so good with the nx350h bought in August 2022. Beware though of getting a car off the lot in the cold winter and the battery probably has previously gone dead.
I bought a new car in January some years ago and a few months later it wouldn't start. After the second trip to the dealer they replaced the battery.

ptung07

Update: while getting the DC-DC recall I had them check it 12v battery. It was bad so they replaced it

gamma742

Was it replaced under warranty? the 12v

ptung07

yes under warranty

twitte

I have a 2022 Lexus NX450h+ with 15K miles.
Problem 1: My wife and I got in the car a couple days ago. The car wouldn't start. Nothing lit up, it was dead. Doors had locked after we got in. The windows were up and the sun was cooking us in the car. We couldn't figure out how to get out of the car. I called Lexus Roadside Assistance, they transferred me to someone that could help me but after I explained the problem they hung up. We eventually figured out that when the car is dead you have to pull the lock lever twice to open the door. Ugh.
Problem 2: We got out and closed the doors and went inside to call Lexus Roadside Assistance again. We noticed that when we closed the doors they were locked again. Lexus said they would send someone over to jumpstart the car and help us get in. Meanwhile I took out the manual key and read the Lexus manual on how to get in. I put a credit card in the space on the driver's door lock and pried the small plastic piece up. I almost broke it trying to get it off (later found out you pry it up then push from the right side and it pops off). Ugh. The manual wasn't very clear. I put the key in and turned it to the right to unlock the door but nothing happed. I ended up calling the service department at my local Lexus dealer and they told me to also pull the black plastic piece on the left under side of the drivers door to open it. This was not very clear in the owner's manual (at least to me).
Note: The Autoclub driver that Lexus called arrived, opened the front hood and placed his jump starter on the special red terminal near the fuses (right side). He then opened my rear hatch to get to the 12V battery, then removed his jump starter and placed it on the battery. The car started right up and I drove it to the dealer. They kept it for 2 days and didn't find anything wrong with the battery, electronics or any drain problem with the battery.

I found it very frustrating to try and get out of the car or in the car when in a hurry and with a dead battery. Good thing the car wasn't on fire. I don't know why Lexus made it so complicated. A simple door latch like they use to have would have been more intuitive to get out. Also when unlocking the car from the outside how about just turning the key. Why the extra step to pull another plastic lever?
I now own a voltage tester (Autder on Amazon for about $15) and jump starter (GooLoo GT4000S for about $100). I guess I should also by a trickle charge to complete my set of problem avoidance tools.
Other than the above, my car has been great!

I noticed a lot of people saying they had to craw through the seats to get to the back hatch in order to open it. Please note what the Autoclub guy did for me to open the hatch without crawing through the car.

NX450Guy

This 12 v battery Achilles heel in what is otherwise an amazing vehicle is a shame. Had the same dead battery issues at 90 and 300 miles until I learned to keep it on “ready” instead of ACC or off with doors/rear hatch open. If you don’t drive a lot, you have a better chance of a semi drained battery that can only give you enough juice to keep a door open for 15-20 minutes. People who drive more tend to not discover this dead battery surprise. But I haven’t had a problems since. Interestingly, my battery was able to be jumped from under the hood, no opening the back to get to the 12 volt.

lsft

You could jump from the hood. No need to open the trunk to jump the car. What I have observed. If you drive short distances - keep the car running idle to at least 15 mins. I still haven't found the sweet spot, but it seems like there is constant drain with the electronics. If you have a dashcam that runs even after you turn off the vehicle that also drains. You approaching the car with your keys - it drops as well. If you don't lock your car, the safety exit assist remains running until the message appears. I am a bit confused with how the system works, but shortly I will have an updated video on some interesting observations.

NX450Guy

Yes, I keep it on ready in general if I’m working/ washing, tinkering with it for more than a couple minutes. Haven’t had any dead batteries since. I do not have parasitic drain from my dealer installed dash or anything, but as you mentioned, there are some surprising 12 volt juice draws where you would least expect. I don’t charge at home, but the fact that leaving your charging cable connected after it tops off the traction battery drains the 12 volt for example. As long as the charging cable is plugged it, it is monitoring the car, even when charging is done. Looking forward to another of your very helpful videos!

twitte

Could you please confirm that if the battery is dead that you can still jump start from the special connection under the front hood? I read somewhere that you had to go to the battery if it was really dead.

What about trickle charging and/or regular battery charging. Can it also be done from the special connection under the front hood?

Thanks.

FireFire

Jump connector is inside the fuse box. Just open it up and there is a big red terminal. It should apply to all the Toyota/Lexus hybrid vehicle.

lsft

Normally you can boost from the front inside the fuse box. I have tried before that if you plug it in and boost immediately it may not work. You need the booster to send enough juice to the battery in the back to boost. If the front does not work, then you would try the back. But most cases the front will do the job.

lsft

This might be spam as I have posted on another thread. But this one is relevant as well

twitte

Well it happened to me again (2nd time now). The battery was dead when I went out to get in the car. I just drove the car about 40+ minutes the day before without any problems. I was now prepared, knew how to open door and jump start the car using my new GooLoo GT4000S jump starter. The only issue I had was the car dash was telling me to unplug the battery cable. I thought it was talking about the jump starter cable and when I took it off the battery posts under the front hood everything shut down. Then I remembered I had the Level 2 Charge cable plugged into the back right side of the car. Once I unplugged that cable everything worked fine and it let me start the car. Duh!

Car is being evaluated at the Lexus Dealership. Last time they told me everything was fine (battery, drain on battery, etc.). I hope to pick it up next week and see what the problem might be.

NX450Guy

Did you know leaving the charging cable plugged in after the charging is done drains the 12v battery? As long as the charge cable is plugged in, the computer is on to monitor charge status. When actually charging, there is juice being diverted for this. But as soon as the car stops charging, the power to monitor is coming from your 12v only. Leave the charging cable in long enough, you drain it.

twitte

Yes thanks, I read about that. However I don't have a battery charger or trickle charger. I only have the jump starter to be used for a few minutes when trying to get the car running. So nothing has been plugged into the car that could be draining it. The Lexus dealer (last time) checked and confirmed that there is minimal drain on the 12 volt battery from all the devices in the car.