basw

Hi, I have a consistent problem with my 2005 Lexus ES330 in the winter. After sitting overnight, the car fails to start and eventually the battery just dies after a few attempts with the starter. The lights and everything else won't turn on. I have replaced the battery twice and still had issues and was scared that I was not able to get to work all last winter! I want to fix this problem this month before winter comes. A mechanic looked at the alternator and tightened the belt and said the alternator shouldnt be the issue.

LeX2K

Not a smart mechanic get the alternator tested, or at least get the voltage tested with the engine running.

VicSWFL

Greetings:

Tightening the alternator belt, possibly tighter than it should be, can be the source of new problems such as excessive wear on the bearings in the alternator. Simply putting the leads of a voltmeter on the battery when the engine is running will tell you if the alternator is putting out. The voltage will be noticeably higher than the battery shows when the engine is not running. If the alternator is putting out as is should, it appears you have an excessive drain on the battery when the car is off. This possibility could be chased by pulling fuses one by one and placing the probes of an ammeter across the fuse terminals to see if there is a current draw where there shouldn't be any with the car off. Harbor Freight sell a suitable test meter for under $10.

Good luck,

Vic
Fort Myers, Florida
2003 ES300 Millennium Silver w/120k miles