This problem has baffled me for months and I really need some advice on that. I firstly noticed the problem that my car would not start due to a dead battery in January, but did not really take it seriously as I let the car sit for 2 weeks and the average temp in January was around 10 degrees. I jumpstarted the car and everything seemed fine. However, I do not use my car very often(about every 10 days) and when I want to use the car, I would always face a dead battery and have to jumpstart the car. This dead battery situation has been going on for the last 3 months and my question is: how long do the batteries on these cars usually last if I leave it sit still? I heard that on some cars the battery would last for at least a month without giving the owner a starting problem, which makes me really wonder if I am facing a normal situation or not.

Also, I have used my portable jumpstarter to start the car for several times, would this damage the battery? I should also add that I once used the car after leaving it parked for 6 to 7 days and the car starts fine, now I am really at a loss here.

 

You might try disabling the Smart Key system when you aren't using the car. Especially if the key fob is stored fairly close to the car when not in use.

 

Hi Bradland, I am pretty sure my 2001 LS430 does not have a Smart Key system.

 

I don't think it is bad for your battery as it is probably shot anyway. I believe jump starting a car is bad for the alternator or starter solenoid.

 

You might want to use a battery tender and plug it in when the car will sit for more than a few days. Also, you can get an accessory cable that attaches to the battery terminals and allows you to connect/disconnect without opening the hood. About $40.

I have been using AGM batteries in my LS's for a long time and find it minimizes this problem.

 

AGM it.....

 

Battery is likely weak. It is not good for them to get totally discharged. Go get the battery and charging system tested for free - takes 10 minutes - I use Walmart for this (only thing I use Walmart is for car batteries). You may need a new battery.

In terms of parasitic draw - you need to look at any non OEM electronics that may be installed - alarms, remote starters, amps, custom lights, blue tooth devices, power points, etc. (even if the item supposedly was taken out) - in the vast majority of cases battery draw when the car is off and locked is due ti some electronic add-on item wired in hot. If you have smart key there is a button to turn it off. There have been some reports of a trunk light staying on in rare instances. You can check by opening rear seat door into trunk.

Regardless suggest you drive the car for 15-20 minutes at least once a week.

 

+1 Get the battery checked, a deep discharge has likely killed it or at minimal shortened it's lifespan. A battery maintainer is $35-$125 depending how many features desired and the name on them. Good purchase for those cars that aren't driven regularly. Hook it up every 7-10 days and it will preserve the battery from those deep discharges.

 

Agree with having the battery load tested. The car should be able to sit for months. I'm losing track of time but my LS430 has been sitting 3-5 weeks, I would not expect it to not start. My wife's car sat just over 31 days, started right up. We have 2 Costco batteries now and I swear by them. The Lexus one is going on 4 years and still good.

 

How old is the battery? Older than 4 years it’s probabably due for replacement.

Get it load tested if in doubt before spending money on battery tenders, etc.

 

If it were my car, if the battery has any issues I would replace it. Now you have a good starting point. .. After, as suggested above, get a battery maintainer which should be standard for anyone who doesn't use their car regularly. I own 3 CTEK maintainers. My LS430 (although these days is being used less) is a daily driver. I do remember though, that once I get past the 2 1/2 year mark and the car does sit for over a week or more, it starts showing symptoms of slightly slower cranking and I immediately get it replaced. 3 years in Florida is Max life for most batteries. If not using the car regularly a maintainer is a must. It's easy to set it up with the connectors, permanently to the battery, and it's convenient there after to plug it in. Good luck.

 

Agree with @Bocatrip . My 2.5 yr old battery was dead beyond revival after a remote start install and it sitting for 3 weeks. Without a remote start they should last a good 3-4 years. A new battery solved my problems and now I know its new. under $100 from Walmart for a 24F with 5 year warranty. The LS may take a couple of cranking attempts even with the new battery to initially start but then it will be OK.

Be prepared though the battery tie down on the LS430 is messed up. The rear will stay in place but the front one has no where to attach to the battery tray. I thought it was just my car but lots of folks had this issue after a battery replacement. I even took out the battery tray and there is absolutely no hole for the front tie down to hook onto!

 

The front tie down does not attach to the tray. Rather, it goes thru a hole in the metal structure in front of the battery. The battery should always be secured.

 

Awesome finally someone who knows where it goes! @jayclapp pls explain where this metal structure is as I cant seem to find it. Thank you

 

The structure I am refering to is the structure that the fuse box is bolted to. The hole is about 7 inches down from the top of the fuse box/or battery. The hook on the rod is then faced forward to the hole, opposite the adjunct side of the battery, and less than an inch away.