Dead 12v battery Incident (merged threads)
Instructor
Joined: Nov 2023
Posts: 972
Likes: 636
From: California
If you or anyone else can answer the following question that put me in bad position after I found the car dead of Friday 6/21: After the 2nd failure I put jumper cables in the trunk. After I opened the driver's door I found I could not open any rear doors or the trunk door. I am physically incapable of reaching the inside rear door openers or climbing over the seat into the back. I felt as if I was in a 3 stooges movie (and I was Curly). From the handbook I could find how to lock the back doors but not to open them. Does anyone know how to do this?
I bought a Schumacher on Amazon and got it in 8 hours. Thanks. I'll make sure it's in the glove compartment. My thinking was: Do I want to die of heat stroke for want of a $100 item? No. I hope the glove compartment doesn't auto lock.
Thanks to all helpful posters pcm888usa,jahnjva and wrinkle in particular
I bought a Schumacher on Amazon and got it in 8 hours. Thanks. I'll make sure it's in the glove compartment. My thinking was: Do I want to die of heat stroke for want of a $100 item? No. I hope the glove compartment doesn't auto lock.
Thanks to all helpful posters pcm888usa,jahnjva and wrinkle in particular
Driver School Candidate
Joined: Jun 2024
Posts: 18
Likes: 5
The best way to jump start is from under the hood, given all the rear hatch limitations in the car's dead condition. The places to attach the cables under the hood are in this post (as from manual, requiring a long enough cable) and also potentially the location indicated by this post. I don't believe the glove box auto-locks.
Driver School Candidate
Joined: Jun 2024
Posts: 18
Likes: 5
The only way to open a rear door with the battery dead is to pull the inside rear door latch lever twice.
The only way to open the rear hatch without power is from the inside and requires one get to the rear cargo area and use a procedure from the manual which requires tools.
The only way to open the rear hatch without power is from the inside and requires one get to the rear cargo area and use a procedure from the manual which requires tools.
If you are alone and not very limber, as I am, you're out of luck. Just make sure you have everything you need in the front where you can reach it. I knew about the rear door latch but I couldn't for the life of me, reach it.
Be glad you don't have a passenger whose wheelchair is in the trunk.
Last edited by warlock; Jun 23, 2024 at 02:45 PM. Reason: grammar
Rookie
Joined: Oct 2023
Posts: 33
Likes: 38
From: TX
Brgds
K
The only way to open a rear door with the battery dead is to pull the inside rear door latch lever twice.
The only way to open the rear hatch without power is from the inside and requires one get to the rear cargo area and use a procedure from the manual which requires tools.
The only way to open the rear hatch without power is from the inside and requires one get to the rear cargo area and use a procedure from the manual which requires tools.
I did once have to manually release the powerless rear hatch - it is practically impossible without folded rear seats, so forget the accessing dead 12V battery unless the car is jumpstarted from the front .
Brgds
K
Last edited by kitlz; Jun 24, 2024 at 02:59 PM.
9th Gear
Joined: Jul 2022
Posts: 9
Likes: 7
From: Tennessee
Second dead RX 450H+ incident
Just had my second dead 5 month old RX 450H+ incident. This time the dealer said the 12 V battery had a “bad cell” and replaced the battery. My wife has a 24 NX 450H + with similar use pattern and had no issues. I love the RX but I need a reliable car. If it happens again I’m asking for a buy back.
Racer
Joined: Oct 2023
Posts: 1,274
Likes: 1,067
From: CA
Check out the Deep Dive video at 12:30 for more information on the keyhole cover.
Instructor
Joined: Nov 2023
Posts: 972
Likes: 636
From: California
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Instructor
Joined: Nov 2023
Posts: 972
Likes: 636
From: California
To those who may not have already noticed, a member posted specific actionable information told to them by Lexus technician at dealership to keep the smart key fob at least 9 feet away from the car when parked (say at home garage). I posted how I additionally prevent signal transmission between the keyfob and the car (which would wake up and cause to exchange signals with keyfob) and drain the 12 V battery. with 5 amps of parasitic current. Others in the forum have also done the same, but the 9 feet specification of separating the keyfob from the car is good information to have.
Driver
Joined: Jul 2023
Posts: 68
Likes: 21
From: CA
So is it really confirmed that leaving your charging cable attached after the Traction Battery has been fully charged will significantly drain your 12V battery?? I’m finding it annoyingly inconvenient to have to babysit this process for a few hours in order to rush out and unplug once it’s fully charged. Would be great just to plug it in at night after a trip and not have to worry about it until next morning.
Racer
Joined: Oct 2023
Posts: 1,274
Likes: 1,067
From: CA
Leaving the vehicle plugged into the EVSE isn't a significant increased discharge when compared to leaving the fobs too close to the vehicle or the other random vehicle wakeup events I've seen that can discharge the battery in hours or a few days. Leaving it plugged in overnight is not an issue. I believe the warning is to prevent leaving it plugged in for more than a few days.
Pole Position
Joined: Sep 2019
Posts: 2,179
Likes: 443
From: CA
Tested today and tested the voltage. The loss is minimal when keeping smart key 9 ft or more away from vehicle or find a faraday box/pouch that works.
Driver School Candidate
Joined: Jun 2024
Posts: 18
Likes: 5
To those who may not have already noticed, a member posted specific actionable information told to them by Lexus technician at dealership to keep the smart key fob at least 9 feet away from the car when parked (say at home garage). I posted how I additionally prevent signal transmission between the keyfob and the car (which would wake up and cause to exchange signals with keyfob) and drain the 12 V battery. with 5 amps of parasitic current. Others in the forum have also done the same, but the 9 feet specification of separating the keyfob from the car is good information to have.
"The vehicle goes to 40mA when vehicle goes to sleep, vehicle will go to 120mA if keys are brought within 10 feet of vehicle and after about 10 minutes will go back to sleep/ 40mA."
This test was done on or about 05/20/24.
The technician told me that the key was detected at a fraction over 10 feet (I forget the inches) and that a smart key for another vehicle (presumably Lexus) also woke the car at about 10 feet.
How significant is a draw of 120mA? I don't know, but I'm sure somebody here has an opinion.
Intermediate
Joined: Oct 2023
Posts: 438
Likes: 342
From: CA
In a test for battery drain by the key the dealer found that:
"The vehicle goes to 40mA when vehicle goes to sleep, vehicle will go to 120mA if keys are brought within 10 feet of vehicle and after about 10 minutes will go back to sleep/ 40mA."
This test was done on or about 05/20/24.
The technician told me that the key was detected at a fraction over 10 feet (I forget the inches) and that a smart key for another vehicle (presumably Lexus) also woke the car at about 10 feet.
How significant is a draw of 120mA? I don't know, but I'm sure somebody here has an opinion.
"The vehicle goes to 40mA when vehicle goes to sleep, vehicle will go to 120mA if keys are brought within 10 feet of vehicle and after about 10 minutes will go back to sleep/ 40mA."
This test was done on or about 05/20/24.
The technician told me that the key was detected at a fraction over 10 feet (I forget the inches) and that a smart key for another vehicle (presumably Lexus) also woke the car at about 10 feet.
How significant is a draw of 120mA? I don't know, but I'm sure somebody here has an opinion.
