120 mA is not the end of the world, but its still about 3 times what should be the "normal" draw for these cars at about 30-40 mA in sleep state (noted as 40 mA specifically above). Definitely way better than 5 Amps told to websurfer, by their dealer/technician. However, its best to be conservatively safe, given that this is a messy problem - and therefore probably also best to place the key within a faraday pouch/bag - unless you can keep the key like 20 feet - 30 feet away. Keeping the key in a Faraday pouch/box at night ensures that the distance wouldn't matter, so long the key is in the box/pouch.

your battery is normal, dont worry. in fact the battery on rx500h can not stand over 2 weeks If you just park there without driving...

120mA is not a big draw, draining a full 60 A-H battery in 20 days, or the more typical half-full battery in 10, but what I've seen is something different. I can't measure the current draw, but when I get around 6' from the vehicle, the voltage rapidly drops almost half a volt, implying a much heavier draw.

I've not seen steady drops like that when the key fobs are about 20' away but I've seen intermittent ones of similar nature that stopped when I moved the fobs over 30' away. I can't be certain it was the fobs' fault as random drops occur at other times. It could have been coincidence. I did try it twice though. Thinking I'll try again now that it's behaving.

Lately, the vehicle has been well-behaved with only rare spikes down and only a 0.19v drop in 72 hours. The charging algorithm is the same though.

Of course, I still don't trust it and still charge it when it gets below 12.4 volts or about once a week.

As you approach the vehicle, the Smart Key receiver detects your key and turns on the outer foot lights located on the underside of the outer door handles. So, keep in mind that each time you walk past your vehicle, the computers wake up and the courtesy lights switch on.

I make sure to only have a fob in my pocket when using the vehicle. I wonder if other fobs wake it up too, but some of the repeated random wakeups are far to frequent to be only fobs. I feel that some other transmissions must also wake it up such as Bluetooth or WiFi. It can't be just any transmission though, because it will go days without a wakeup while other times, it will wake up so frequently as to pull the battery down a full volt in 12 hours. It's been well behaved for a few weeks now though.

Went to use the car this afternoon and battery dead once again. Lexus replaced the battery in February…just a bit frustrating. At least this time was able to get in the car, but needed the booster get the hatch released and open. Currently on a charger😡😡

What was the replacement battery (brand, Ampere-hour) that Lexus/dealer replaced with ?

I retained the Panasonic battery because I didn't think my battery was the problem (poor charging algorithm, combined with parasitic drain is)

I am not seeing anything in reference to Panasonic. 84 month battery….right now I’m not seeing that it’s going to last more than 5 months. I reset the auto-shutoff to minimum settings and shut off the digital key.

Thanks for sharing - looks its Lexus badged, so probably re-branded from a battery maker. It has 540 CCA, relative to 345 CCA of the stock/OEM from factory. I seem to remember another person stating that the dealer gave them an Interstate battery.

So its becoming increasingly clear with hard evidence that the battery isn't the problem (for most people), as the new battery is also dying. Getting an AGM out of pocket may band-aid the problem somewhat, going by the NX450H+ owner's experience and couple folks on Reddit, but I'm trying the key-in-Faraday pouch, proactive charging only once a month avenue first. I didn't want to deal with the dealer, who are clueless about the real problem anyway. I've not had a second dead-battery after the winter episodes when the temperature dropped to 4 C. I drive about 100 miles every week, so admittedly, there is frequent use of the car (hence charging happening, however, inefficient that charging is, during use), and I kept the fob in Faraday pouch - but have not been charging with maintainer (or remote starting the car) more than once per month intervals. I have turned off digital keys, and rear-seat reminders, but kept all other reminders (i.e. windows open, etc) on. Have turned off Clean Assist and Drive Pulse - to serve dual purposes of turning off useless app features that collect location and driving data and can be misused, while also potentially draining the 12 V.

So with the above, I have not had a dead battery in the last 3-4 months. I was thinking of getting an AGM before winter, but if the above "hygiene" keeps the battery alive, will have to see if I need an AGM.

I was trying to remember what the cca was of the previous battery and I had it in my mind it was around 350, so I think you’re correct on there. I have disabled the digital key and set the auto shutoff timers to the minimum. Near as I can tell, the Lexus app on my phone is unable to communicate with the car, so I’m hoping no draw is there.
There was someone who mentioned a hardware change….think it was a DCM that may have cured his issues. Not sure what a DCM is….

Clean assist?? Drive pulse?? I don’t recall anything about those features.

Hey MP,
Sorry to hear this. Did you start the hybrid system off the booster? When AAA has done this and I ran the car for only a few minutes, it started normally the next time I tried it. (including the next day).

Since the car was in our garage, I used the booster long enough to get the rear hatch open and used the charger to charge the battery. This old charger was wigging out as the battery was pulling over the 10amps the charger was designed to put out. I ended up removing the positive cable and the draw was down to 8amp. I think there was some systems on after I initially hit the start button.

I believe by DCM they are referring to the "Data Communication Module" - unlikely to be the problem unless you are having very frequent (like multiple times per week or every week) dead car.

Clean Assist and Drive Pulse are accessible through the app - switched them off by going into my "Account" after clicking the headshot icon on the top right of the phone app screen. So that the car is not required to send these useless location data and other stuff to the servers. So right now, I just have those settings on that I actually need/use - such as alerts for having left the windows etc. open, but none of the other nuisance.

Reviewing the posts 12v battery incidents on this thread, victims are carrying some or all of the following:
Faraday cages for your keys, a fully charged jump starter, jumper cables for use with another vehicle or battery, a trickle charger for use at suitable intervals. Be sure you can get to them if the car is dead. Never touch your car or carry Lexus keys or your phone in your own garage unless you are there to use the car. Turn off Clean Assist and Drive Pulse etc. I run the car remotely for 10 minutes before I use it in the morning - just because you're paranoid it doesn't mean you car isn't trying to kill you.

If the weather is extreme do not stop in a lonely place, e.g. a rest stop without air conditioning (Summer) or heating (Winter). Remember you will need 911 services if have even a moderate unsheltered wait in heat or cold. Today, in NV or AZ, you'll get heat stroke with about 20 minutes exposure.
Consider carefully whether you should transport very old or very young passengers alone or anyone with medical conditions including dementia.
Take care.

Doesn't sound like fun does it?

I am relieved to find that in my short 45 days of ownership, my battery monitor has never reported less than 90% charge for the battery.... including a period of two weeks while I was on vacation. I plan to keep monitoring for a while, but I'm not losing sleep from fear of being stranded abroad or at home.