Dead Battery, An Hour Later Good Battery, An Hour Later Dead Battery..

[MomsBad-es300]

Registered to see if ANYONE can help! My Mom's 2002 ES300 with 55,870 miles starts in the morning and is driven three miles to Target. Return to car and battery is dead. AAA jumps and off she goes to get her hair done. Hair is done and car starts fine and she is off to Costco. Returns to car and battery is dead. AAA jumps and she goes home. Next day no problems. Next day no problems. Next morning battery is dead. And on and on. Sometimes the car works fine for a month or two and then WHAM it is back to the dead battery routine.

This has been happening for two years. In November 2008 Lexus repair does a parasitic drain test and no anomalies are found. In January 2009 Firestone believes the alternator is bad and replaces it and the battery. Seven days later battery is dead again and Firestone replaces batter for free. So far 3 new batteries from Firestone and about to go get fourth. July 7, 2010 I took it to an auto electrical specialists and they do a drain test for 36 hours and find nothing irregular. I pick up car, starts fine, go to a store and return and car starts fine and go to lunch and return and battery is dead! Return to auto electrical specialists and they do another drain test for 24 hours as well as test alternator and starter. Everything checks out. Drive car home and no less than one hour later my Mom goes out to start it and...the battery is dead!!! Other than that the car is perfect! Does ANYONE have ANY ideas as to why this happens.

[gbhrps]

You need to get someone to check out the starting system of the car. There is a bad ground or corroded terminal somewhere.

There is also the possibility that the starter has a bad section on its armature. If the starter works and then stops on a good section of the armature, it will have the battery strength to spin and start the next time. But if it stops on the bad section after a successful start, the next start attempt may need more battery strength to get the armature to spin past the bad section, and that is when you need to get a jump. A friend's car had this exact issue several years ago. GoodLuck!

[schan1w]

Could be a loose connection on the battery terminals. Are you sure the battery is really "Dead" or is it just that the car doesn't start.

[oguitar]

Is the electrical system stock. Meaning has anyone installed any thing electrical like an aftermarket radio of gauge of some kind?

[lexis lexus]

Registered to see if ANYONE can help! My Mom's 2002 ES300 with 55,870 miles starts in the morning and is driven three miles to Target. Return to car and battery is dead. AAA jumps and off she goes to get her hair done. Hair is done and car starts fine and she is off to Costco. Returns to car and battery is dead. AAA jumps and she goes home. Next day no problems. Next day no problems. Next morning battery is dead. And on and on. Sometimes the car works fine for a month or two and then WHAM it is back to the dead battery routine.

This has been happening for two years. In November 2008 Lexus repair does a parasitic drain test and no anomalies are found. In January 2009 Firestone believes the alternator is bad and replaces it and the battery. Seven days later battery is dead again and Firestone replaces batter for free. So far 3 new batteries from Firestone and about to go get fourth. July 7, 2010 I took it to an auto electrical specialists and they do a drain test for 36 hours and find nothing irregular. I pick up car, starts fine, go to a store and return and car starts fine and go to lunch and return and battery is dead! Return to auto electrical specialists and they do another drain test for 24 hours as well as test alternator and starter. Everything checks out. Drive car home and no less than one hour later my Mom goes out to start it and...the battery is dead!!! Other than that the car is perfect! Does ANYONE have ANY ideas as to why this happens.

Wow, amazing story. I'd had set the car on fire and then collected insurance....

One thought to add to the other suggestions. Could be a bad interior light door switch which sometimes is leaving the interior lights on. Hard to tell it's happening during the day, easy at night.

LL

[coalsmoke]

Something like this happened 2 or 3 times to my '93 es300. Once the battery went from fully charged to dead flat in a couple of hours for no apparent reason. One thing I noticed was that each time it happened, I had left the key in the ignition. Now I make a point of removing the key every time I stop the engine. Months later, there has been no further trouble. The cause? What I suspect is the mechanism that tilts the steering wheel up when you switch off. If the mechanism was sticking there might be a drain as the solenoid (or whatever works it) tried to move the wheel. Just a theory!