I understand the "two week discharge" but my battery has discharged overnight three days in a row!! I put it on charge and it brings it right up. Temps at night do not drop below 50F so that should not be a problem. All lights are OFF, Walmart has checked the battery and declared it good. So what would kill it overnight that I am missing???? Need answer quick. Its my only working car!

 

I may have found the problem. The trunk lid was open. Hard to see just looking at it. But I am surprised the light in the trunk could kill the battery overnight! Anyone else experience this???

 

Experienced the same thing once when I had regular bulbs and left the map light one overnight. Any lights that are regular incandescent will drain your battery quick if left on for long period of time. If you can switch out all the bulbs for LED's. They don't generate heat thus will not drain the battery so quickly if it happens again. All my lights are LED's.

 

Your door open warning light in the dash should have been illuminated. I know mine is when my trunk is not closed all the way.

 

Take it to get tested at a battery shop...it may be a bad cell.

 

yes, in fact i was going to say "the problem is most likely your trunk light." It used to be a common problem on the board until people put in LED's. Unlike the interior lights that will eventually go off, the trunk light stays continually lit.

 

Where do you get the trunk LEDs? What is the nomenclature?

 

As I saiid, I took it to Wallmart and it was fine.
But now I need some LEDs for the trunk!!

 

Not that I have any issues with LEDs, but isn't the real solution to just make sure your trunk is closed. There is a light on the dash that tells you that.

 

No, the light tells you SOMETHING is open. When I saw it was on, I was driving at 60mph so just said to myself, "need to check the trunk" 20 min later I was home and had forgotten all about it. Your brain does that after a while, just tunes out that which is not a current problem.......When I turned off the ignition it went away. Better for it to be fool proof.

 

Oh OK glad it worked out!! Go get 'em!!!

 

Problem solved!!! Domt ever trust ANYONE!!!!!!!
When the problem started I had Wallmart check the battery...."Its fine, just needs a charge, charger is fine, starter is fine" , was the answer. Two days later I had to call AAA to come start the car. "Battery is fine, just needs a charge" said "the man from AAA". I let it idle in the driveway for 30 minutes then want to the store (10 miles) . twenty minutes of shopping, it was dead again. Recalled AAA and they didnt want to do a second start in one day but I convinced them that "their guy" had told me it was fine and had no problems so they sent him out again. Drove straight to Wallmart and they checked the battery....surprise, surprise...it needed replacing this time.

NEVER TRUST ANTONE!!!!!!!!! The battery was a gonner and the experts were telling me it was fine! Its working fine now.....I think.....

 

My motto. 😁 What happened to you is rare. But it does happen. My guess is that the load tester they used for the battery didn't test it to its max cranking Amps.
I recently had a battery fail on a friends LS. Took it to the local auto parts and they said they could test to 500(?) cranking Amps. The battery is fine. But, they did warn me that they couldn't really test it to its max power capabilty.

Paul

 

My Lexus LS430 had a similar problem we wound up having to take it to the dealer and we're told that it was the navigation module to replace it was ridiculous to have it removed was included with the price of the diagnostic 69 bucks that fixed it

Best

Sandy

Owner of two cars one SC430 2002 the other LS430 2003