My 05 TL ate its second battery in less than a week. I have already disconnected the HFL more than a year ago because of that killing a battery.

What else could now be causing the battery to die? The car has 165,000 miles, all stock. Still has the original alternator. Was getting set to take it in for a new timing belt service but now have to figure this part out first.

Thanks for any info you can provide.

 

It's hard to diagnose a dying battery over the internet. Why don't you have your mechanic to a parasitic draw test?

 

Did you ever get it checked?

 

Is your alternator putting out the proper voltage/working correctly?

 

Yes, the dealer checked it while in for a timing belt change. Determined to be the alternator. Had that swapped and so far seems to be good.