Battery Dying
08-21-21, 03:23 PM
#61
Ah, I missed the part about you already replacing the battery once. So presumably that rules out the battery, odds are against getting two successive bad batteries.
I wonder if there is some possibility of an intermittent charging issue in the car, that doesn’t show up under routine testing but somehow manifests itself while driving?
Alternative idea: some intermittent current drain while parked, something that didn’t show up when they ran the parasitic drain test. Is there a second key fob that could be in the vicinity? Or is the Lexus app connecting to the car?
I wonder if there is some possibility of an intermittent charging issue in the car, that doesn’t show up under routine testing but somehow manifests itself while driving?
Alternative idea: some intermittent current drain while parked, something that didn’t show up when they ran the parasitic drain test. Is there a second key fob that could be in the vicinity? Or is the Lexus app connecting to the car?
08-21-21, 05:12 PM
#62
Rookie
Thread Starter
Ah, I missed the part about you already replacing the battery once. So presumably that rules out the battery, odds are against getting two successive bad batteries.
I wonder if there is some possibility of an intermittent charging issue in the car, that doesn’t show up under routine testing but somehow manifests itself while driving?
Alternative idea: some intermittent current drain while parked, something that didn’t show up when they ran the parasitic drain test. Is there a second key fob that could be in the vicinity? Or is the Lexus app connecting to the car?
I wonder if there is some possibility of an intermittent charging issue in the car, that doesn’t show up under routine testing but somehow manifests itself while driving?
Alternative idea: some intermittent current drain while parked, something that didn’t show up when they ran the parasitic drain test. Is there a second key fob that could be in the vicinity? Or is the Lexus app connecting to the car?
The problem manifests when the car is parked, locked, not driven over multiple days. Hence, it is not related to anything that happens when the car is driven. The key fobs are kept very far away from the car. I don't have any extra hardware connected to the car and I don't use any Lexus apps. What Lexus computers do on their own may well be the problem.
Intermittent current draw is exactly what I think is happening (this is what I told Lexus). The problem is how to prove it AND, more importantly, how to prove that it is not normal (as claimed by Lexus). Right now I don't have a concrete example from even *one* RX350 owner who is specifically not experiencing the problem I am observing. It is not common for people to not use their car for six days or more and not common for people to measure the battery voltage over time, as I have done. However, it clearly happens that cars are left unused when people fly somewhere on an extended vacation, have other cars that they drive, etc. Hence, the examples should be out there. This is what I am looking for.
08-22-21, 04:24 AM
#63
It is theoretically possible that the first battery died simply because of all the time it was unused (not charged) from the time the car was assembled through shipment, through sitting at the dealer's lot. So possibly it was unrelated to the current problem (but I think it was related).
The problem manifests when the car is parked, locked, not driven over multiple days. Hence, it is not related to anything that happens when the car is driven. The key fobs are kept very far away from the car. I don't have any extra hardware connected to the car and I don't use any Lexus apps. What Lexus computers do on their own may well be the problem.
Intermittent current draw is exactly what I think is happening (this is what I told Lexus). The problem is how to prove it AND, more importantly, how to prove that it is not normal (as claimed by Lexus). Right now I don't have a concrete example from even *one* RX350 owner who is specifically not experiencing the problem I am observing. It is not common for people to not use their car for six days or more and not common for people to measure the battery voltage over time, as I have done. However, it clearly happens that cars are left unused when people fly somewhere on an extended vacation, have other cars that they drive, etc. Hence, the examples should be out there. This is what I am looking for.
The problem manifests when the car is parked, locked, not driven over multiple days. Hence, it is not related to anything that happens when the car is driven. The key fobs are kept very far away from the car. I don't have any extra hardware connected to the car and I don't use any Lexus apps. What Lexus computers do on their own may well be the problem.
Intermittent current draw is exactly what I think is happening (this is what I told Lexus). The problem is how to prove it AND, more importantly, how to prove that it is not normal (as claimed by Lexus). Right now I don't have a concrete example from even *one* RX350 owner who is specifically not experiencing the problem I am observing. It is not common for people to not use their car for six days or more and not common for people to measure the battery voltage over time, as I have done. However, it clearly happens that cars are left unused when people fly somewhere on an extended vacation, have other cars that they drive, etc. Hence, the examples should be out there. This is what I am looking for.
You can spend a lot of time & money on this and perhaps never solve it. What I'd suggest is get a "Smart Charger" and recharge the battery every week, these chargers also desulfate the battery.
08-22-21, 10:49 AM
#64
Pole Position
This kind of problem is soooo time consuming to resolve if it can be resolved, it plagues all modern cars. For the dealer it's more expedient and cheaper to put in a new battery than to solve the problem. This parasitic draw is a blight we all encounter sooner or later.
You can spend a lot of time & money on this and perhaps never solve it. What I'd suggest is get a "Smart Charger" and recharge the battery every week, these chargers also desulfate the battery.
You can spend a lot of time & money on this and perhaps never solve it. What I'd suggest is get a "Smart Charger" and recharge the battery every week, these chargers also desulfate the battery.
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rx20info (08-22-21)
08-22-21, 11:51 AM
#65
Rookie
Thread Starter
I understand this suggestion and I wouldn't suggest that it is a bad idea, however this is a new car and you shouldn't have to put up with this. The manufacturer should stand behind the car, especially while it is still on warranty! Period. End of discussion. Even if it isn't an easy problem to troubleshoot! Do a search in the 6th generation ES forum and you will see a couple of very lengthy threads where members had the same issue with this parasitic power drain. Lexus eventually figured it out but not before it seriously frustrated many owners - and I'm sure factored into their next automotive purchase decision.
There are a couple of messages in the ES forum reporting being able to start the car after letting it sit for two weeks! Unfortunately, they, of course, had no reason to measure the battery voltage at that point so it's hard to know whether there was really significant charge left or it was marginal.
I guess I will need to spend some more time on the various Lexus forums to see what is there regarding similar problems.
In the ES forum there are some reports that the drain may be affected by radio frequency signals in the environment. The Lexus technical specialist suggested that. Hence, I got them to repeat my measurements at the dealer over two days and their results matched mine! However, instead of them then agreeing to look further, they just ignored these results and repeated the mantra: "there is nothing wrong with your car".
08-22-21, 12:49 PM
#66
Since I don’t drive my 2020 RX with 9200 miles on it much. It’s been sitting for 3 days in the garage so far. I measured with my multi meter and got 12.3volts. I’ll measure everyday until my wife decides to drive it. The car is parked in the garage and never been connected to a battery tender or ever had to be jumped. car was purchased new march of 2020.
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rx20info (08-22-21)
08-22-21, 01:36 PM
#67
Rookie
Thread Starter
Since I don’t drive my 2020 RX with 9200 miles on it much. It’s been sitting for 3 days in the garage so far. I measured with my multi meter and got 12.3volts. I’ll measure everyday until my wife decides to drive it. The car is parked in the garage and never been connected to a battery tender or ever had to be jumped. car was purchased new march of 2020.
Since we don't know exactly what was the charge at the beginning of the period, it is not possible to compare that single measurement to the results I got (I started with a fully-charged battery). However, if you can get one or two more measurements, they should be comparable. If the discharge curve with your car follows mine, after one more day you will get 12.26V and after another day 12.22V or 12.23V.
What was the procedure you used to measure the voltage? I ask since the current draw while you are measuring the voltage has a significant impact on the voltage. When you open the door in order to pop the hood that "wakes up" computers and the current draw increases to hundreds of mA. What I do is: pop the hood, lock the car, take the key fob to a distant location, and wait 30min for the computers to go back to their quiescent state. After all that I measure the voltage with a multi-meter (while the key fob is not on me -- still far away). I then close the hood and repeat 24 hours later.
If you do something different and describe it, I will follow your procedure in order to get comparable measurements.
08-22-21, 03:26 PM
#68
If you’re going to get a battery tender anyways, go ahead and install the quick-connect dongle on the battery, leaving the connection accessible at the front grill. Then you can measure voltage directly off the dongle, without having to open the door or pop the hood. Of course leave the key fob far away too.
08-22-21, 08:23 PM
#69
Instructor
Thanks! Actually, I am not looking for people with the the same problem. I am looking for people who do *not* have the problem. 4,000 miles in 9 months is actually quite a bit of driving (100 miles per week). If I was driving that much consistently, I would definitely not have the problem either. What is the longest time you have let the car sit without driving it at all?
08-22-21, 10:01 PM
#70
Thank you very much! This is really helpful.
Since we don't know exactly what was the charge at the beginning of the period, it is not possible to compare that single measurement to the results I got (I started with a fully-charged battery). However, if you can get one or two more measurements, they should be comparable. If the discharge curve with your car follows mine, after one more day you will get 12.26V and after another day 12.22V or 12.23V.
What was the procedure you used to measure the voltage? I ask since the current draw while you are measuring the voltage has a significant impact on the voltage. When you open the door in order to pop the hood that "wakes up" computers and the current draw increases to hundreds of mA. What I do is: pop the hood, lock the car, take the key fob to a distant location, and wait 30min for the computers to go back to their quiescent state. After all that I measure the voltage with a multi-meter (while the key fob is not on me -- still far away). I then close the hood and repeat 24 hours later.
If you do something different and describe it, I will follow your procedure in order to get comparable measurements.
Since we don't know exactly what was the charge at the beginning of the period, it is not possible to compare that single measurement to the results I got (I started with a fully-charged battery). However, if you can get one or two more measurements, they should be comparable. If the discharge curve with your car follows mine, after one more day you will get 12.26V and after another day 12.22V or 12.23V.
What was the procedure you used to measure the voltage? I ask since the current draw while you are measuring the voltage has a significant impact on the voltage. When you open the door in order to pop the hood that "wakes up" computers and the current draw increases to hundreds of mA. What I do is: pop the hood, lock the car, take the key fob to a distant location, and wait 30min for the computers to go back to their quiescent state. After all that I measure the voltage with a multi-meter (while the key fob is not on me -- still far away). I then close the hood and repeat 24 hours later.
If you do something different and describe it, I will follow your procedure in order to get comparable measurements.
Hopefully, my wife will cooperate and have nowhere to go this week. we’ll see….
08-23-21, 07:41 PM
#71
The way to properly test your current draw is with a pico mA Amp clamp and the pico oscilloscope. This equipment is not cheap so you have to find a technician who has it. The oscilloscope is $950 and the ammeter is $115. I have both of these items and have used them occasionally.. What you do is clamp the ammeter to your negative battery cable then that connects to the oscilloscope which is connected to a laptop computer. The laptop must have the pico software installed. You start the program and the ammeter will pick up any current flowing and send that signal to the oscilloscope which processes it and sends it to the laptop then saves it to a chart. This can be done for a period of time e.g. 10 minutes or 1 hour or 10 hours. It all gets saved to the laptop. This will tell you how much current is being drawn over a period of time. The duration of time is set by you. Any variations in current will show up on the chart created by the software on the laptop. Very high tech and very cool. If you lived by me I would do for you no problem and for free. It may sound a little complicated at first but it isn't too bad.
See if you can find a mechanic near you that has this capability.
See if you can find a mechanic near you that has this capability.
Last edited by jcg0324; 08-23-21 at 07:48 PM.
08-23-21, 08:13 PM
#72
Rookie
Thread Starter
The way to properly test your current draw is with a pico mA Amp clamp and the pico oscilloscope. This equipment is not cheap so you have to find a technician who has it. The oscilloscope is $950 and the ammeter is $115. I have both of these items and have used them occasionally.. What you do is clamp the ammeter to your negative battery cable then that connects to the oscilloscope which is connected to a laptop computer. The laptop must have the pico software installed. You start the program and the ammeter will pick up any current flowing and send that signal to the oscilloscope which processes it and sends it to the laptop then saves it to a chart. This can be done for a period of time e.g. 10 minutes or 1 hour or 10 hours. It all gets saved to the laptop. This will tell you how much current is being drawn over a period of time. The duration of time is set by you. Any variations in current will show up on the chart created by the software on the laptop. Very high tech and very cool. If you lived by me I would do for you no problem and for free. It may sound a little complicated at first but it isn't too bad.
See if you can find a mechanic near you that has this capability.
See if you can find a mechanic near you that has this capability.
The only other possibility besides intermittent current draw is, as a few people suggested, that the battery capacity (Ah) is not what it should be even though the battery passes a CCA test.
The challenge with both of these possibilities is to find a technician/mechanic with the equipment and knowledge to perform the appropriate tests. It seems that there must be such people in Los Angeles, where I am located. If anybody has any suggestions how to find them, please let me know.
08-24-21, 06:49 PM
#73
Thank you very much! This is really helpful.
Since we don't know exactly what was the charge at the beginning of the period, it is not possible to compare that single measurement to the results I got (I started with a fully-charged battery). However, if you can get one or two more measurements, they should be comparable. If the discharge curve with your car follows mine, after one more day you will get 12.26V and after another day 12.22V or 12.23V.
What was the procedure you used to measure the voltage? I ask since the current draw while you are measuring the voltage has a significant impact on the voltage. When you open the door in order to pop the hood that "wakes up" computers and the current draw increases to hundreds of mA. What I do is: pop the hood, lock the car, take the key fob to a distant location, and wait 30min for the computers to go back to their quiescent state. After all that I measure the voltage with a multi-meter (while the key fob is not on me -- still far away). I then close the hood and repeat 24 hours later.
If you do something different and describe it, I will follow your procedure in order to get comparable measurements.
Since we don't know exactly what was the charge at the beginning of the period, it is not possible to compare that single measurement to the results I got (I started with a fully-charged battery). However, if you can get one or two more measurements, they should be comparable. If the discharge curve with your car follows mine, after one more day you will get 12.26V and after another day 12.22V or 12.23V.
What was the procedure you used to measure the voltage? I ask since the current draw while you are measuring the voltage has a significant impact on the voltage. When you open the door in order to pop the hood that "wakes up" computers and the current draw increases to hundreds of mA. What I do is: pop the hood, lock the car, take the key fob to a distant location, and wait 30min for the computers to go back to their quiescent state. After all that I measure the voltage with a multi-meter (while the key fob is not on me -- still far away). I then close the hood and repeat 24 hours later.
If you do something different and describe it, I will follow your procedure in order to get comparable measurements.
i checked the voltage when I got home yesterday evening and got exactly 12.26volts. Unfortunately when I came home from work today the car was gone. The wife decided we needed groceries. So the 12.26 volts was on the 4th day in the garage. Sorry rx20info I gave it a shot.
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rx20info (08-24-21)
08-24-21, 09:25 PM
#74
Rookie
Thread Starter
i checked the voltage when I got home yesterday evening and got exactly 12.26volts. Unfortunately when I came home from work today the car was gone. The wife decided we needed groceries. So the 12.26 volts was on the 4th day in the garage. Sorry rx20info I gave it a shot.
So, it looks like over one day the discharge curve in your car precisely matched the discharge curve in mine.
So now I have to consider the possibility that, perhaps, "there is nothing wrong with my car"...
Or, perhaps, there is something wrong with all/many 2020 RX350s.
12-04-21, 06:06 PM
#75
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Battery - RX 350
Hi all -
First time posting, so I don't know if I am in the right forum for this.
I've owned my RX350 (2021) for about a year now. Since I bought it from the dealership in a new condition, I assume I wouldn't run into any issues with my battery until the 3rd, 4th, or 5th year. However in June, my car wouldn't start because my battery was weak. Today (in December), the same thing happened again. Since I wfh, I don't drive as much as I use to. So that may be the reason why my battery is always weak.
For those of you who managed to keep your RX in good condition for many years and rarely have a problem with the battery, how many miles or how long should I be taking my car out for a ride every single week?
Thanks,
Kathy
First time posting, so I don't know if I am in the right forum for this.
I've owned my RX350 (2021) for about a year now. Since I bought it from the dealership in a new condition, I assume I wouldn't run into any issues with my battery until the 3rd, 4th, or 5th year. However in June, my car wouldn't start because my battery was weak. Today (in December), the same thing happened again. Since I wfh, I don't drive as much as I use to. So that may be the reason why my battery is always weak.
For those of you who managed to keep your RX in good condition for many years and rarely have a problem with the battery, how many miles or how long should I be taking my car out for a ride every single week?
Thanks,
Kathy