I have a 2004 LS 430. The VSC, Brake, Check Engine light coming on occasionally. Mechanic unable to diagnose unless lights are on when I bring it in. This has occurred before and after battery failed and was replaced, it went away for 3-4 months. Lights are coming on again and battery sounds like it is weakening. Any ideas out there?

 

Maybe your alternator is on its way out, your mechanic test it to make sure you its charging the correct amount

 

Get yourself a code reader. Bought one for less than $30 from Amazon. Then you will get a much better idea as to what the problem is.
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