Dead 12v battery Incident (merged threads)
04-07-24, 08:56 PM
#196
My experience suggests that it needs single digit temperatures (4 C in my case) for the problem to show up. So definitely a problem even in California winters.
I did some measurements with my multimeter connected to the jumpstart-connection points of the battery in the hood today, and found that while keeping the car in "Ready" mode does provide charging voltages (13.5 V and above, I think I noticed) to the 12 V battery - I can confirm that charging the PHEV with a Level 2 charger does NOT actually charge the 12 V battery..
I did some measurements with my multimeter connected to the jumpstart-connection points of the battery in the hood today, and found that while keeping the car in "Ready" mode does provide charging voltages (13.5 V and above, I think I noticed) to the 12 V battery - I can confirm that charging the PHEV with a Level 2 charger does NOT actually charge the 12 V battery..
As to charging with the hybrid battery...yes, my point was that you don't need to take the trouble of actually driving around to charge the 12V, just let your car run in the garage (with open door) and the traction battery will charge it. Have done it at times with the Prius when the wife forgot to close a light.
Toyota probably has to give us a way to shut down the various tech (that run even when the car is stopped) when needed so as not to drain the 12V when it gets really cold.
04-07-24, 09:20 PM
#197
Intermediate
As to charging with the hybrid battery...yes, my point was that you don't need to take the trouble of actually driving around to charge the 12V, just let your car run in the garage (with open door) and the traction battery will charge it. Have done it at times with the Prius when the wife forgot to close a light.
Toyota probably has to give us a way to shut down the various tech (that run even when the car is stopped) when needed so as not to drain the 12V when it gets really cold.
Last edited by wrinkle; 04-07-24 at 09:28 PM.
04-08-24, 05:59 AM
#198
Driver School Candidate
If you have time/interest, I’d like to know what you used to get this information. Especially how you got a ‘fuse-by-fuse’ and systems based report.
this looks extremely useful.
thanks
doug
this looks extremely useful.
thanks
doug
04-08-24, 07:22 AM
#199
Driver School Candidate
The downside to the Odyssey units is, obviously, the cost.....they ain't cheap. The upside is that they are not made in China, as are many of the others in the marketplace. There are similar Chinese AGM's for less than half the cost of the Odyssey units. If Odyssey's cost twice the price, are they going to last twice as long? If so, I might go for one (or two, in my case). I see mostly favorable reviews on the Odyssey but, there are a few disgruntled buyers out there, as well. I've seen some people that tried to get warranty service on an item purchased thru Amazon and were refused, as it wasn't purchased directly or thru an authorized dealer network. (not speaking of batteries in this instance). In any event, I am still kicking this idea around.
some companies I have looked into will happily respond to questions about suitability of their ‘drop-in’ LFP replacement.
04-08-24, 08:19 AM
#200
An update on the 2024 RX 450h+ dead-battery/ parasitic draw issue.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
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wrinkle (04-08-24)
04-08-24, 08:36 AM
#201
04-08-24, 09:14 AM
#202
AGM battery is a bandaid
This is more about an "under-designed" reserve capacity of stock battery - which has far too much parasitic drain due to the monitoring/sensing electronics in the car's quiescent state (parked, locked) than its designed to handle, and high sensitivity to low temperature causing voltage drops - as the reasons to consider an AGM having a much greater reserve capacity than the Lexus' stock ones. So its not about having unexpected battery failures, but to get around "expected" battery deaths due to the parasitic drains and cold temperature sensitivity of the stock batteries. The NX hybrid forums have lots of threads about these. And now the RX hybrids and direct measurements too.
There have now been reports of these problems right after the first week of delivery, to a couple months, and in my case at ~4 months age neophyteof the car.
There have now been reports of these problems right after the first week of delivery, to a couple months, and in my case at ~4 months age neophyteof the car.
Also , instruction to help level set some of the more beginner forum users , when you want to tag a forum user start typing the "@" followed by the user name and select from pull down list see the diagram below:
how to tag a forum user
YMMV,
MidCow3
04-08-24, 10:01 AM
#203
Instructor
As for changing the battery type the charging system itself comes into play. I have not talked with anyone that fully understands what parameters it uses in charging the aux battery. It is totally different than the alternator system that will actually fully charge the battery on a trip. I have read on ES forum where mpg was lost by not putting in the right battery. Internal resistance, etc come into play in how this charges. Even the dealer putting in a deep discharging battery probably affects how it charges. The original type should have been put back in unless Lexus high up advised to change.
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wrinkle (04-08-24)
04-08-24, 11:05 AM
#204
Intermediate
A bigger AGM battery is still just a band aid fix. The real problem is parasitic battery drain. @SMartin hit the nail on the head, the main problem "Bluetooth digital key receiver assembly". See his post: https://www.clublexus.com/forums/rx-...l#post11699378. Other. A sources are security systems, theft cameras, etc. Lexus did a really poor job of adding phone profiles and digital keys. And actually the solution is very simple, if the 12 volt battery discharges to a low rate, it could be charged from the traction battery ( obviously , a safety stop if the traction battery is also at a very low charge level)
YMMV,
MidCow3
YMMV,
MidCow3
FWIW, I had the digital key disabled in-car and still had the problem. Don't have any other security system or theft cameras installed, no aftermarket accessories like dash-cam. So yes, its all on Lexus - and we are just trying to find a way of going about lives with band-aid fixes like trickle-chargers and AGM batteries.
There's at least one person in the RX hybrid forum who might ask for proceeding with Lemon law, since he had this problem right on the first week of a RX450H+ delivered.
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StefanoS (04-08-24)
04-08-24, 11:49 AM
#205
Check out my post in the RZ Forum … same 12V battery problem … car has been in the shop for over 3-weeks with no resolution in sight. 😡
04-08-24, 12:48 PM
#206
Intermediate
An update on the 2024 RX 450h+ dead-battery/ parasitic draw issue.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
04-08-24, 01:13 PM
#207
NX has similar problems
No disagreements that bigger AGM battery would be a band-aid fix - and the real fix needs to come from Lexus. That noted, what can we owners of $70K+ bricked Lexi do, when we are now loaded with a turd of a design by "ultra-reliable" Lexus - other than apply a band-aid fix and go about our lives, until and unless Lexus releases a TSB or recall notice to dealers ?
FWIW, I had the digital key disabled in-car and still had the problem. Don't have any other security system or theft cameras installed, no aftermarket accessories like dash-cam. So yes, its all on Lexus - and we are just trying to find a way of going about lives with band-aid fixes like trickle-chargers and AGM batteries.
There's at least one person in the RX hybrid forum who might ask for proceeding with Lemon law, since he had this problem right on the first week of a RX450H+ delivered.
FWIW, I had the digital key disabled in-car and still had the problem. Don't have any other security system or theft cameras installed, no aftermarket accessories like dash-cam. So yes, its all on Lexus - and we are just trying to find a way of going about lives with band-aid fixes like trickle-chargers and AGM batteries.
There's at least one person in the RX hybrid forum who might ask for proceeding with Lemon law, since he had this problem right on the first week of a RX450H+ delivered.
YMMV,
MidCow3
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Julius071 (04-08-24)
04-08-24, 08:27 PM
#208
Locked up RX450h+ with dead battery
An update on the 2024 RX 450h+ dead-battery/ parasitic draw issue.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
Found w/ extensive experimentation at home that there is no apparent input a driver can change to avoid the dead battery or parasitic draw from occurring on this vehicle. Over twenty days tried turning various things off, leaving off, then turning back on. No difference. That includes the Lexus connected services/ Pulse, etc etc. Day by day the unattended vehicle will deplete the 12v battery from 12.6 to 12.1 to 11.7 to 11.4 to dead. Over a matter of a few days, not weeks. Previous RAV4 Prime XSE with every factory bell/ whistle could be left for weeks unattended w/ no discernable impairment.
Just to clarify - temperature should be a non-factor. Kept in an enclosed, insulated garage that during this test period didn't drop below 60F or rise above 70F.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
If it can be found - will share that info here for everyone's benefit.
If it can't be found - will share process of establishing a lemon.
----------------------
As a side note, considered an AGM battery replacement, but am staying w/ the Lexus dealer installed one for lemon paper-trail. AGM certainly seems logical, given it's strengths, and would seem best-suited to what a vehicle like the RX 450h+ requires. But if the mfg chose the battery (lead-acid), and it was designed to run with that battery, the system(s) should work as designed. Previous RAV4 Prime did. Might still install an AGM in the end, just to test the weekly results. Simple-enough solution, but doubt it could prevent the parasitic draw that is occurring. If the draw issue isn't resolved - the AGM would become a more-expensive paper weight.
04-08-24, 11:39 PM
#209
I have not had that problem, but a quick search finds that it is fairly common in quite a few late model cars.
In one post from 2019 from here, the dealership said this:
I took the car to Lexus who apparently never thought of putting an amp meter to each fuse terminal. Apparently the Car amplifier draws .25 amp when car is shut down which apparently is 5 times the normal for the entire car. They recommend to change the amplifier for about Cdn $750. This is after 4 years of checking and 3 batteries later
Someone with better voltage monitoring equipment might want to check that.
Great! A permanent solution to this potential problem would be better than trickle chargers and larger aux batteries.
I hope you mentioned it is happening to quite a few people, so they don't dismiss it later as being an isolated problem.
In one post from 2019 from here, the dealership said this:
I took the car to Lexus who apparently never thought of putting an amp meter to each fuse terminal. Apparently the Car amplifier draws .25 amp when car is shut down which apparently is 5 times the normal for the entire car. They recommend to change the amplifier for about Cdn $750. This is after 4 years of checking and 3 batteries later
Someone with better voltage monitoring equipment might want to check that.
An update on the 2024 RX 450h+ dead-battery/ parasitic draw issue.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
I've left the vehicle at the Lexus dealership for them to monitor and test/ experiment with for a week+ . They have begun talking with "Lexus Engineering" about the issue, and I'm assuming will try various logical tests to track down what the draw is.
I hope you mentioned it is happening to quite a few people, so they don't dismiss it later as being an isolated problem.
Last edited by asj2024; 04-08-24 at 11:46 PM.
04-09-24, 07:48 AM
#210
Intermediate
What is meant my the amplifier there ? Music system ? Does that mean disabling audio when parking might be the solution ?
If you have the original link of the post from 2019, please do share that
If you have the original link of the post from 2019, please do share that