I have a 2007 Lexus RX350 and the last three batteries have lasted 2 years or less. Correct battery for car. My alternator is putting out 13.59 volts. Is that enough to keep the battery going? I am told it needs to be higher or the same thing will continue.
Should be 14V plus.. Have the alternator tested at your local auto parts store.
The specs for your car is 13.7 to 14.2 volts, do what Tom suggested, Lexus seem to have voltage regulator problems, mine did, even the genuine Lexus replacement didn't last long, got one from a local rebuilder and that cured the problem.
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