Dead 12v battery Incident (merged threads)
#136
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Don't hold your breath for an OTA update. This is Lexus not Tesla. Since this car came out in Dec22-Jan23 there has only been one OTA update just about a month ago and they updated very little. Since this issue isn't extremely wide spread it probably wouldn't get very high priority.
#137
Driver School Candidate
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Add me to the list. Our battery died after a particularly cold spell. The dealer ‘tested’ the battery and said nothing wrong. We were advised to get a trickle charger because we don’t drive it enough. Apparently, not driving it for 2 weeks, we should expect the battery to go flat. Seriously, leaving the car at the airport for a 3 week vacation might leave us stranded.
my solution was to get a NOCO booster (GB70, actually) and have it charged up in the back of the car. The good news is I now know how to access the key slot for the car. (And they’ve replaced the drivers door handle with the ‘new’ handle that doesn’t freeze in cold weather - will wait for the next sub zero day to test it out-here’s hoping)
my solution was to get a NOCO booster (GB70, actually) and have it charged up in the back of the car. The good news is I now know how to access the key slot for the car. (And they’ve replaced the drivers door handle with the ‘new’ handle that doesn’t freeze in cold weather - will wait for the next sub zero day to test it out-here’s hoping)
#138
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Add me to the list. Our battery died after a particularly cold spell. The dealer ‘tested’ the battery and said nothing wrong. We were advised to get a trickle charger because we don’t drive it enough. Apparently, not driving it for 2 weeks, we should expect the battery to go flat. Seriously, leaving the car at the airport for a 3 week vacation might leave us stranded
Most things I've read say 2 weeks is at the border or beyond.
https://www.jdpower.com/cars/shoppin...out-driving-it
https://autoexhaustandtyres.co.uk/ne...ry-sit-unused/
#139
Driver School Candidate
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I’ve never had a car go flat, after sitting at the airport for a week without being started.
i think it’s pretty clear that they spec’ed the battery based on the 4 cylinder engine ‘assumed demands’ for starting.
my wife told me at the last service appointment they tested the battery when it was cold. It failed and so, was replaced.
if the parasitic demands for these cars is that high, they need a decent sized battery, not just the minimum CCA to start this small engine.
i think it’s pretty clear that they spec’ed the battery based on the 4 cylinder engine ‘assumed demands’ for starting.
my wife told me at the last service appointment they tested the battery when it was cold. It failed and so, was replaced.
if the parasitic demands for these cars is that high, they need a decent sized battery, not just the minimum CCA to start this small engine.
#140
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Add me to the list. Our battery died after a particularly cold spell. The dealer ‘tested’ the battery and said nothing wrong. We were advised to get a trickle charger because we don’t drive it enough. Apparently, not driving it for 2 weeks, we should expect the battery to go flat. Seriously, leaving the car at the airport for a 3 week vacation might leave us stranded.
my solution was to get a NOCO booster (GB70, actually) and have it charged up in the back of the car. The good news is I now know how to access the key slot for the car. (And they’ve replaced the drivers door handle with the ‘new’ handle that doesn’t freeze in cold weather - will wait for the next sub zero day to test it out-here’s hoping)
my solution was to get a NOCO booster (GB70, actually) and have it charged up in the back of the car. The good news is I now know how to access the key slot for the car. (And they’ve replaced the drivers door handle with the ‘new’ handle that doesn’t freeze in cold weather - will wait for the next sub zero day to test it out-here’s hoping)
![Smilie](https://www.clublexus.com/forums/images/smilies/smile.gif)
Curious as to whether this problem has been occurring with anyone who has a base RX 350 (2.4l Turbo), or is it something peculiar to the RX hybrids. (350h, 450h+, 500h)?
Last edited by Markfm; 03-25-24 at 04:53 PM.
#141
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Just checking - is yours an "h" version RX, and it's the main engine compartment battery that was dead?
Curious as to whether this problem has been occurring with anyone who has a base RX 350 (2.4l Turbo), or is it something peculiar to the RX hybrids. (350h, 450h+, 500h)?
Curious as to whether this problem has been occurring with anyone who has a base RX 350 (2.4l Turbo), or is it something peculiar to the RX hybrids. (350h, 450h+, 500h)?
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Markfm (03-25-24)
#142
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Do we actually know there is a problem? There are no actual stats on this. I have yet to encounter it, and I've left my 450h+ unused for 5 days straight one time. I've also been driving it relatively few times, most on short trips (at one month old, I only have 300+ miles on it, and that includes 200+ miles when I drove it from dealer). No problems. I have a feeling it's all the tech gizmos running all the time even when the car is left unattended, so hopefully if there is a problem, an OTA will solve it.
#143
Intermediate
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I might have an interesting experiential data-point to add.
I just returned from a 26 days overseas trip, when I didn't have physical access to the car, which was left locked in my home garage. I fully expected to return from the trip, after a 20+ hour long flight, to have to deal with a dead 12 V battery, based on everything reported and discussed here - I'm convinced this is a marginal design problem by Lexus, fully validated by WellsB's excellent measurement data as above - and fully agree that it isn't something one should have to worry/think about in a premium "Lexus reliable" vehicle.
I had prepared by placing my jump starter and long cable (to reach the negative connect point of the engine block) in the front passenger area, so that I can access it easily after prying open the dead, manual door once I got back.
I had also found the excellent hack by WellsB great - to periodically remote start the car every 7 days using the App (I had charged the traction battery to 87 % before leaving) - so that it switches to "Ready Mode" that then charges the 12 V before it goes dead. The only problem was - I didn't realize that the car prevents remote starting if the inactive period exceeds 7 days. You can't do remote start if the car has been "off" for longer than 7 days - and I specifically tried this remote start hack at the 12 day interval, to space out the interval - and found out the hard way that I couldn't, as I had exceeded 7 days of inactivity before trying. Also, you can't do remote starts more than twice in succession, without physically opening/closing doors after that. So that hack doesn't work for longer than 14 days, to remotely charge the 12 V, in hindsight (without battery maintainer, which I find to be a chore, and trying to avoid unless I have to).
In any case, I got into the garage this morning - and to my utter surprise, found the car/battery alive ! It was able to unlock and switch to ready mode fine, which I left the car in for about half an hour, and even switched on the ICE during that for good measure - before driving out with the car. I wish I were able to gather the 12 V battery's voltage data at the point, but I was not prepared for that... (although prepared for the dead battery).
I think what saved the day was the fact that I was in waning NorCal winter, when the temperature isn't dropping too low, unlike in Canada or Northeast US - and maybe (just maybe) the 7 day inactivity puts the car into a deeper sleep mode with lesser 12 V drain (which, if a feature, would explain why one wouldn't be able remote-start after 7 days of inactivity). Whew!
In any case, at least one datapoint that was a positive surprise.
I just returned from a 26 days overseas trip, when I didn't have physical access to the car, which was left locked in my home garage. I fully expected to return from the trip, after a 20+ hour long flight, to have to deal with a dead 12 V battery, based on everything reported and discussed here - I'm convinced this is a marginal design problem by Lexus, fully validated by WellsB's excellent measurement data as above - and fully agree that it isn't something one should have to worry/think about in a premium "Lexus reliable" vehicle.
I had prepared by placing my jump starter and long cable (to reach the negative connect point of the engine block) in the front passenger area, so that I can access it easily after prying open the dead, manual door once I got back.
I had also found the excellent hack by WellsB great - to periodically remote start the car every 7 days using the App (I had charged the traction battery to 87 % before leaving) - so that it switches to "Ready Mode" that then charges the 12 V before it goes dead. The only problem was - I didn't realize that the car prevents remote starting if the inactive period exceeds 7 days. You can't do remote start if the car has been "off" for longer than 7 days - and I specifically tried this remote start hack at the 12 day interval, to space out the interval - and found out the hard way that I couldn't, as I had exceeded 7 days of inactivity before trying. Also, you can't do remote starts more than twice in succession, without physically opening/closing doors after that. So that hack doesn't work for longer than 14 days, to remotely charge the 12 V, in hindsight (without battery maintainer, which I find to be a chore, and trying to avoid unless I have to).
In any case, I got into the garage this morning - and to my utter surprise, found the car/battery alive ! It was able to unlock and switch to ready mode fine, which I left the car in for about half an hour, and even switched on the ICE during that for good measure - before driving out with the car. I wish I were able to gather the 12 V battery's voltage data at the point, but I was not prepared for that... (although prepared for the dead battery).
I think what saved the day was the fact that I was in waning NorCal winter, when the temperature isn't dropping too low, unlike in Canada or Northeast US - and maybe (just maybe) the 7 day inactivity puts the car into a deeper sleep mode with lesser 12 V drain (which, if a feature, would explain why one wouldn't be able remote-start after 7 days of inactivity). Whew!
In any case, at least one datapoint that was a positive surprise.
Last edited by wrinkle; 03-25-24 at 10:36 PM.
#144
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In any case, I got into the garage this morning - and to my utter surprise, found the car/battery alive ! It was able to unlock and switch to ready mode fine, which I left the car in for about half an hour, and even switched on the ICE during that for good measure - before driving out with the car. I wish I were able to gather the 12 V battery's voltage data at the point, but I was not prepared for that... (although prepared for the dead battery).
In any case, at least one datapoint that was a positive surprise.
In any case, at least one datapoint that was a positive surprise.
Also good info on remote start having limit of 2x in succession, and with 7 day max limit.
I'm actually tempted to leave the car for a week and see what happens, just as an experiment. Turn off as much electronics as possible (eg manually turn off all the safety features that use sensors, though those should switch off automatically when car is shut down).
Maybe someone with a multimeter can do this:
https://www.alldata.com/diy-us/en/di...itic-draw-test
Last edited by asj2024; 03-26-24 at 01:56 AM.
#145
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Adding another data point to this thread.
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
#146
Instructor
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Adding another data point to this thread.
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
#147
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Adding another data point to this thread.
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
Brand new 2024 RX 450h + essentially dead on (delivery) arrival. Had to jump start the vehicle twice in first week of ownership.
Have checked daily for anything "on". Haven't found anything yet. Have tried keeping the vehicle both "locked" and "unlocked" overnight; no difference.
Local Lexus dealer (excellent team) tested the system, suspected just a dud battery, replaced w/ a deep-discharging version of the 12V. They tested for parasitic draws for two hours prior to replacing 12v battery; nothing showed up.
Said let's try the 'replace battery' route for now, and watch.
Still have a voltage drain however. This new battery is being depleted each night. Down from "new battery" charge to 11.76v at this point, and dropping daily.
Anyone have recent Lexus experience servicing parasitic draws, and likely device/ circuit candidates ?
Sad to think such an expensive vehicle needs two plug-ins daily: one for the hybrid PHEV battery system, and one - to trickle charge the 12v ? Back to the Future, eh ?
#148
Instructor
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Damn that a huge voltage drop! Sadly, I am preparing for the dead battery situation in my 23 RX 500h. Currently researching to change out OEM battery for a Odyssey Battery with wife approval pending. for me, why bother when we can change out oem battery under warranty at the dealership?!
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#149
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So what am I missing, we bought Lexus vehicles, not market-entry-level products ?
Please don't misunderstand me, my wife enjoys the comfort and amenities of our RX350h very much. At least 2-3 time a week I have people asking me about the RX line and how I like the vehicle.
But should it be put upon the vehicle owner to keep some or any of the following items on hand because the battery dies or becomes discharged too low to start.the vehicle:
- Portable battery jump starter,
- Battery changer or trickle charger,
- Battery charger harness installation,
I didn't see any of these items listed as add-on options for the vehicle.
Thanks in Advance,
DEL92
RX350h Premium Plus / Eminent White Pearl
Please don't misunderstand me, my wife enjoys the comfort and amenities of our RX350h very much. At least 2-3 time a week I have people asking me about the RX line and how I like the vehicle.
But should it be put upon the vehicle owner to keep some or any of the following items on hand because the battery dies or becomes discharged too low to start.the vehicle:
- Portable battery jump starter,
- Battery changer or trickle charger,
- Battery charger harness installation,
I didn't see any of these items listed as add-on options for the vehicle.
Thanks in Advance,
DEL92
RX350h Premium Plus / Eminent White Pearl
#150
Instructor
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
So what am I missing, we bought Lexus vehicles, not market-entry-level products ?
Please don't misunderstand me, my wife enjoys the comfort and amenities of our RX350h very much. At least 2-3 time a week I have people asking me about the RX line and how I like the vehicle.
But should it be put upon the vehicle owner to keep some or any of the following items on hand because the battery dies or becomes discharged too low to start.the vehicle:
- Portable battery jump starter,
- Battery changer or trickle charger,
- Battery charger harness installation,
I didn't see any of these items listed as add-on options for the vehicle.
Thanks in Advance,
DEL92
RX350h Premium Plus / Eminent White Pearl
Please don't misunderstand me, my wife enjoys the comfort and amenities of our RX350h very much. At least 2-3 time a week I have people asking me about the RX line and how I like the vehicle.
But should it be put upon the vehicle owner to keep some or any of the following items on hand because the battery dies or becomes discharged too low to start.the vehicle:
- Portable battery jump starter,
- Battery changer or trickle charger,
- Battery charger harness installation,
I didn't see any of these items listed as add-on options for the vehicle.
Thanks in Advance,
DEL92
RX350h Premium Plus / Eminent White Pearl
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asj2024 (03-26-24)