Battery Problems
Thread Starter
Driver School Candidate
Joined: Jun 2015
Posts: 8
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From: Missouri
Battery Problems
I have a 2003 LS430 with 57000 miles on it. If the car is not driven every 5 to 7 days, the battery goes dead. If anyone has experienced this problem, I would appreciate hearing from you. Thanks
Thread Starter
Driver School Candidate
Joined: Jun 2015
Posts: 8
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From: Missouri
I failed to mention that the battery has been replaced 3 times in the last 5 years. I thought the problem might be the little light that shows that the anti-theft system is armed, but the Toyota dealer says no.
Racer
Joined: Jan 2011
Posts: 1,761
Likes: 250
From: AZ
There's clearly a draw somewhere, the "old school" way was to hook a test light between the car battery's negative cable and negative post and pull fuses until the test light goes off, but with newer cars there is sometimes enough of a draw that you have to use a multimeter
Pole Position
Joined: Mar 2008
Posts: 2,146
Likes: 70
From: Illinois
The "draw" could be the alternator not putting out enough amps to recharge the battery. I'd have the alternator checked first by a reputable technician, before you spend time trying to track down a short somewhere. While your mileage (57K) isn't typical of alternator failure on the LS, you are in a hotter climate than snow belt folks, and heat alone can take its toll on the alternator.
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Lead Lap
Joined: May 2006
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The "draw" could be the alternator not putting out enough amps to recharge the battery. I'd have the alternator checked first by a reputable technician, before you spend time trying to track down a short somewhere. While your mileage (57K) isn't typical of alternator failure on the LS, you are in a hotter climate than snow belt folks, and heat alone can take its toll on the alternator.
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Driver School Candidate
Joined: Jun 2009
Posts: 36
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From: Georgia
Dead battery syndrome - 05 LS430
270k miles
Dead battery syndrome for 2 years. Toyota replaced combo controller which drew heavily on battery at operating temp. Problem solved--for several months.
Dead battery syndrome for 2 years. Toyota replaced combo controller which drew heavily on battery at operating temp. Problem solved--for several months.
Tried indy mechanic. Very thorough. Found no parasitic draws. Tested many components, removing each for a separate, component only test apart from the vehicle environment. Examined all fuses. Nothing.By chance he found a wiring harness behind the engine with a worn wire--contact friction. Repaired wire, secured harness away from engine.Also found on/off switch under dash. Flipped off.Unfortunately both these were done together. One or both seem to have fixed problem. Finished last week of March, 2017. So far, so good.
Lexus Test Driver
Joined: Sep 2016
Posts: 8,588
Likes: 392
From: PA
270k miles
Dead battery syndrome for 2 years. Toyota replaced combo controller which drew heavily on battery at operating temp. Problem solved--for several months.
Dead battery syndrome for 2 years. Toyota replaced combo controller which drew heavily on battery at operating temp. Problem solved--for several months.
Tried indy mechanic. Very thorough. Found no parasitic draws. Tested many components, removing each for a separate, component only test apart from the vehicle environment. Examined all fuses. Nothing.By chance he found a wiring harness behind the engine with a worn wire--contact friction. Repaired wire, secured harness away from engine.Also found on/off switch under dash. Flipped off.Unfortunately both these were done together. One or both seem to have fixed problem. Finished last week of March, 2017. So far, so good.
Driver School Candidate
Joined: Mar 2017
Posts: 14
Likes: 0
From: Colorado
Are you using the SmartKey? The car sends out a signal looking for the SmartKey on a regular basis. If you don't drive the car very often this will drain the battery. Turn off the SmartKey by clicking the button under the dash on the right side and see if that helps, or you can always trickle charge the car when its in the garage.
Lexus Test Driver
Joined: Sep 2016
Posts: 8,588
Likes: 392
From: PA
Are you using the SmartKey? The car sends out a signal looking for the SmartKey on a regular basis. If you don't drive the car very often this will drain the battery. Turn off the SmartKey by clicking the button under the dash on the right side and see if that helps, or you can always trickle charge the car when its in the garage.
Driver School Candidate
Joined: Mar 2017
Posts: 14
Likes: 0
From: Colorado
The previous owner of my LS had a similar battery drain issue that disappeared once he turned off the SmartKey. I don't know how long it should last between starts but between the SmartKey, security and whatever else they have running all the time I can imagine the battery would die eventually. I assume you can leave the SmartKey in the car and it may stop the constant pinging from teh car looking for the key, but thats just a guess.
The manual has a page about disabling SmartKey if the car is going to sit for an extended period of time so they must know its an issue.
The manual has a page about disabling SmartKey if the car is going to sit for an extended period of time so they must know its an issue.
Lexus Test Driver
Joined: Sep 2016
Posts: 8,588
Likes: 392
From: PA
The previous owner of my LS had a similar battery drain issue that disappeared once he turned off the SmartKey. I don't know how long it should last between starts but between the SmartKey, security and whatever else they have running all the time I can imagine the battery would die eventually. I assume you can leave the SmartKey in the car and it may stop the constant pinging from teh car looking for the key, but thats just a guess.
The manual has a page about disabling SmartKey if the car is going to sit for an extended period of time so they must know its an issue.
The manual has a page about disabling SmartKey if the car is going to sit for an extended period of time so they must know its an issue.