rcpeters

Three times now in the last year, my wife has parked her LS430 while at work and returned to find the battery completely dead. Could not even electrically unlock the doors. The first time, we took the car to the dealer to test the electrical system after I recharged the battery, no problems found. The next time a few months later, we suspected the Costco battery must have been the problem, so we got a replacement. A few days ago, it happened again, so I recharged the battery and everything is fine for now.

We think my wife is leaving the lights on by slightly moving the stalk switch from "auto" to "on". I tested this by turning the lights on, and locking the car. The lights did not go off. So I guess, it is very important to have the light switch set clearly to "Auto" or "off". Also, there is another stalk switch that I suppose if for fog lights, but with that on, I don't see any lights. The day time running lights go off with the key off.

Anyone else experience problems with good alternator, "battery symbol" going off when the car starts, and after hours of being parked the battery goes dead?

kenny b

My 02 UL has a trickle charger on it. The previous owner told me he put it on cause the battery went dead on him a couple of times after leaving the car for a week or so. He was told that this happens because there are several electrical components that continue to draw on the battery even when the car is not running. Don't know if this is true or not but I plug it in when I'm driving the car for a couple of days- no problems so far. hope this helps
It also helps cause its soooo cold up here- it was minus 21 C today or around-5 Degrees for you guys in the states.

braunfels

I have the same thing going on with my 06 430. I left the car in the garage for about three weeks and today the battery is dead. This is the 2nd time in just over a year. I'll jump it and bring it back to the dealer tomorrow. Maybe they'll have an idea of what the problem is...maybe not. If I find out anything, I'll post it here.

Boomer01

I used to leave the keys in my car when in the garage. This would cause my battery to get low because the car senses the key when it is within 15 feet (I think). You can tell because the red security light will blink when the key is near. This could be some of your problems.

braunfels

You may be on to something. My key is just inside a door from the garage to my house and the distance is about 10-12 feet. I've seen the red security light blinking and didn't think anything of it.

I didn't go to the dealer today, so nothing to report. When I do go later this week, I'll ask them about your theory and report back.

HornyLlama

This happened to me over the weekend. I have an 03 and hadn't driven it in a week or so. Was installing new tailights and the battery just died. No lights were on or anything. Oh well at least it seems like a somewhat common problem. Time for a new battery.

usermel

Wow, I have a 2001 LS430 and had battery issues as well.I wasn't leaving the lights on at all and had the battery replaced after 3 times having it go dead. The 3rd time the battery went dead it no longer could be charged at all! New battery was actually given to me by the dealership! Haven't had a battery issue in the year since I was given new battery! Hope you get this resolved and I'd ask dealer for the best battery to use in your LS430 and buy it!L.G.N.M

usermel

Also, I stopped locking my doors when I'm parked in my garage as well. It may help not to lock your door if/when car is parked in the garage! L.G.N.M

GS4_Fiend

iTrader: (22)

If the battery symbol is on while driving. It means the alternator is not charging the battery. Which will cause the battery to be drained. FYI, what you all could do is check the brain drain after shutting the car off. Get a Digital Multi Meter, put it in milliamps (mA). Disconnect the negative battery cable. Put the leads in series one lead on the negative post of the battery and one lead to the negative cable that goes on the battery. Remember, it MUST be in series! As in you have to disconnect the negative cable battery. Put the meter in milliamps (mA) and check for the amp reading. If it reads more than .060 amps, something is causing that drain. You would have to go get it checked. GL! It's not promising, but it's something good to know!

braunfels

Well, I finally made it to the dealer yesterday after jump starting my car
(06 430). As I drove it the 30 miles, I looked for any signs of indicator lights that might be hints to the problem...didn't see any. The dealer supposedly checked out the electrical system, and found no problems either.

My service rep at the dealer said this about the problem: "Oh yeah, 430s frequently have battery issues if you don't drive the car every day". She says that's because 430s "have so many sensors that the car is constantly checking". She suggested that I hook up the battery to some kind of charger while it's parked in the garage. I asked about the smart key theory, and she didn't think that was really the cause. By the way, when I carefully read the section on the smart key system in my owners manual, I found a statement that said you should disable the system if you don't drive the car for more than 14 days. It did not say that the battery would be drained otherwise, but I think you could easily draw that conclusion.

So...I have disabled the smart key system using the switch under the dash, and will see if I still have a problem when I haven't driven the car for awhile. I'm not 100% convinced this is the remedy, but I'll see.

Swagga82

i would say this never happen to me and i left my car sittin for weeks maybe you should invest in a yellow top battery

bigcory

There is a lot of info about this that i've seen before.

First, I had my battery die on my once in the 7 months i've owned the car. The passenger side door was left open slightly. I forgot to lock the door when I went in the house so I did not hear the warning beep that sounds when a door is left open. The interior lights never turned off, and voila, dead battery.

Second: The owners manual also talks about the key causing the battery to die. The car is constanly searching for your smart key (04+ owners). If you don't run the car for several weeks the battery will run out of juice. Manual suggest turning off the smart key if you won't be driving the car for a while.

On a side note, leaving the headlight in the "on" position will not cause the battery to die. They lights should still turn off after the motor has been turned off and the doors locked. Pressing the lock button twice on your remote will shut it off again. Test it out and see if it works on yours, mine is an 05

Bdragon007

I don't know if anyone has the same issue, but I notice when I use the mirrors auto fold feature that's when I would walk out to a dead car. If I turn off the auto fold feature then it's fine, I just replaced a oringinal Lexus battery BTW.

Lexie's LS

Hi gang. This is exactly the discussion I was looking for when I found Club Lexus. Wifey and I just bought an 05 LS430, and it has dead battery syndrome. First stop was the internet to read up--and found we were not alone by any means. Next stop was my personal mechanic, then Auto Zone, and now the car is at the Lexus dealer.

Alternator was pushing less than 14 amps and is still under warranty. So want to deal with that first--and rule out a loose belt--then see where I stand. Still has the original Lexus battery which tests strong.

Have found other LS430 owners who've raised issues similar to the above: lots of electronics, parasitic battery draw (things that run on the battery when the engine is off), confusion about proper light switch placement when the engine is off, etc.

There is a third party add-on electrical device that monitors idle battery draw, keeps the battery from dropping below crank range, and provides surge protection to the vehicle's electronics (seemingly a must-have for navigational system owners). If I continue to have dead battery syndrome after the dealer gets done, I will investigate the purchase and installation of this device and let the forum know how it works out. (Of course I invite any comments on this approach from the forum.)

ohmy

Huh, I thought it was interesting that a dealer had to jump start an LS430 before giving me a test drive last week.