I'm posting for a relative regarding a 2015 Lexus RX 350. It is only driven about 4-5000 miles per year. It is having some kind of battery drain/charging issue. It has been back to the dealer twice now without any resolution. The dealer tests everything battery, charging system, battery drain and comes up with nothing. No lights have some on for charging or anything while driving. I have not found any real issues in researching this problem for this model and year. I found other Lexus models with the "intermittent battery discharge". The dealer says that with all of the electronics on these newer cars they do draw on the battery more and they need to be driven "more" in order for the alternator to re-charge the battery. I don't have details, as it is not my car, but it sounds like after a few days sometimes it will not start. Recently, it was after one day, which seems like an anomaly compared to the rest of the times. In the case of one day and it would not start, maybe something could have been left open or on. The dealer either says "you need to drive it more" or "we can install a battery tender" for you. I feel like since it is under warranty, they don't want to bother with it. My issue is that they have owned it for about 2 years now, and I don't remember these issues the first year of ownership. When it started having this "no start" problem, the battery was replaced, which was probably almost a year ago. It went to the dealer in Nov. 2017 and again in April 2018.

Do they have any known issues with this model?
Is that normal for these cars (Lexus, BMW, Maserati, any higher end name here) to have this kind of issue?
The dealers have to install battery tenders on them if they are not driven enough?
Thoughts on what it might be?

 

these newer cars they do draw on the battery more and they need to be driven "more" in order for the alternator to re-charge the battery.

He's right. Car driven that little does not get enough go juice from alternator but plenty of use from bazillion of electronics in it. For example, EVAP purge pump that turns on several hrs after vehicle was parked and runs for about 20 minutes. Plus all the computers.
You didn't notice it year one as battery then was new and mighty. But, as it gets undercharged and older, it does fade away in its capacities. Also, battery terminals need to be cleaned and lubricated and sealed.
Batteries do not like running low on charge. They deteriorate very fast then.
Just buy a $20 battery tender at Wallmart and have it connected. You can even go green and get solar one.

 

Well the solar one would need the vehicle to be parked out in the sun.

I would also say buy a battery tender. All exotic car owners have them and all infrequently driven vehicles need them. Even the stores who sell batteries have to keep cycling the batteries on the charger [these are brand new batteries which are not supporting any drain].

Salim

 

Once a battery has been allowed to fully discharge (to die), it is damaged and will not function as well as before. So it is possible that they left a door open or something and drained the battery, and now it will not hold enough of a charge to stay alive in-between those infrequent uses.
I don't know if 4 to 5k miles a year is infrequent enough use to cause a problem, unless the battery was already discharged, as I had mentioned, and is now in a weakened state.

If you go to any autozone or similar store, they will test the battery for you. It would be nice to hear a second opinion on the condition of the battery... especially from someone that would not be liable if it needed to be replaced. Most batteries are covered under a 3 to 5 yr warranty.

Some batteries say that the "Vehicle computer system must be reset"... something important to consider as well as some newer cars need to "know" that a new battery has been installed or it will not work right and could damage the new battery. I'm not sure if this applies to the 2015 RX350 though?

 

Thanks for the replies.
ukrkoz - The dealer had recommended the installation of a battery tender, for $200. Yes, I agree, I don't know how many times the "new" battery has been discharged (Walmart battery) that certainly shortens the life. It probably was a better quality battery (original battery) in the first year that they owned the vehicle. Now, with it being driven that little, and a marginal battery - it goes dead. Just like cell phones, etc, it seems like the battery technology is behind all of our electronics draining on our batteries. Still, not a good experience for them with a "fancy" Lexus. 2011 Ford Escape was just fine, battery wasn't dead all the time.

Battery tender ($20) has been installed, and hopefully solves the issue. Just a royal pain in the ***, especially in the winter.

 

I'd have a load test done on the battery. Batteries normally last 5-6 years but some fail earlier, especially if they have been zeroed a time or two. I suspect the battery has developed a weak cell. I had a 2014 RX350 that didn't get driven much, about 1,500 miles a year. It never had a dead battery. $200 for a Battery Tender.

 

I had just assumed that the dealer had replaced it with an OEM battery under warranty.
My 2014 RX350 has an AGM battery...
Knowing car manufacturers, my guess is that Lexus didn't upgrade to the more expensive AGM battery type in the RX-350's just because they had some extra money they wanted to blow... They probably realized that these cars needed it. The dealer is being partially honest with you, as usual. These cars do have higher demands. So if you don't drive often AND if you want to use a cheap battery, then yes you will need a battery tender to keep it alive. The reason they are recommending a $50 battery tender (which they've marked up to $200), is because a cheap battery tender will do more harm than good.

If it were me, I would toss the "new" battery, toss the battery tender, and just buy a good AGM battery (which will come with a 3-5 yr. warranty).
Then just make sure all the convenience lights are off (and leave them that way), set the headlights to auto, and make sure the doors are always closed completely when exiting.

I'd rather spend $250 on a good battery than "save" $250 and have to deal with being stranded with a dead battery, having to hook up/ disconnect a battery tender, and taking the risk of using a cheap battery tender and insubstantial battery in a car with so many sensitive electronics

Just my opinion.

 

I've removed my recommendation for an Optima battery. After looking into the brand more, it's questionable if they are as good quality as they used to be.
I'd like to change my recommendation to an AGM type battery from Costco.

 

Funny that you mentioned Costco. I have purchased Optima batteries over the year. One of them had an early demise (less than 3 years). I went to other retailers and they could tell by looking at the number [batch/model/what_ever] that the battery was made for a 'special vendor'. That special vendor was Costco. Since it was still under warranty Costco gave me some money back which I used to purchase a regular 12v battery. This one developed a shorted cell and took out my alternator.
I have not had much luck with batteries from Costco. I seem to be a unique case as lots of folks have had good luck with their purchases. As far as Costco as a vendor, they have not given me any issue on returns and warranty service.

One of the Optima (red top) I have in my wife's GS is now 12+yrs.

Salim

 

oh man, I'm sorry to hear about your alternator.
I've got the towing prep package with the upgraded alternator and was thinking it's probably gonna cost more than normal to replace that when it comes time.
When I was reading reviews on the Optima batteries someone mentioned that Costco used to carry them but no longer did because of too many returns.
I remember reading years back that Costco had the best batteries... I think it was on consumer reports. I've always bought them since then and have always had good luck with them.
Guess I don't really know enough though to make a solid recommendation on a brand.
Common sense just tells me to stick with that AGM battery type though, that's for sure. So that's the first requirement I'm gonna look for when I replace mine. My almost 5 yr. old OEM battery is still going strong, but I know it's time is gonna come.

 

I saw this today. Not sure if it relates to your problem or not.

https://static.nhtsa.gov/odi/tsbs/20...86305-5448.pdf

 

I have had this problem with a BMW (2006 330cic)-- one thing that helps, along with a battery tender, is to lock the car immediately after turning it off and keeping it locked. Locking the car, I have been told, more quickly starts the process of closing out those electronic items that draw power. I have a solar panel that I put on the dash board and plug into the lighter when it is parked outside. The car is currently in the garage on a tender.