Hey guys, so I have a 2008 LS460, a couple months back in August, I was on E and couldn’t put in gas because I was in a rush (i shoulda put gas) was driving on the freeway for a bit and took the next exit to finally put gas but as soon stopped at the gas pump, the battery light came on. So i pumped gas & drove off, everytime i would drive the battery symbol would go away but when i would break or come at a slow speed it would pop back up again. but then when i almost made it home, every light came on, ac turned off, windows rolled down slow, power steering gone & then the car shut off. Me thinking it was a low battery, I went to autozone to charge the battery & then put it back in, it cranked up and was running until i drove for 10 secs & every light popped up again, no power steering and eletrical problems. After I left it for about a week, the battery went completely bad & no good, so I’m thinking somethings killing the battery but anyways. So now last week this November, got a new battery thinking it was a faulty battery, it cranked up for the first time in months but same thing happened all over again. ANY IDEAS WHAT IT COULD BE?? I’m thinking that it is the alternator but I gave it to a shop & they said it could be a eletrical problem but not sure at all, I ain’t no mechanic at all, at allll but i do a bit research😂, IF ANYONE HAS SIMILAR EXPERIENCE OR ANSWERS PLEASE LMK!!

 

Sounds like a failed alternator

 

With engine running check voltage on the battery terminals. If below 13.8-13.5 then you have alternator problem. If you have 13.8 at the battery terminals with engine running and all these issues are present, then it is something in the power distribution system downstream from the battery. Another scenario is something with the alternator drive belt or belt tensioner. If not enough tension belt will be slipping, alternator won't be rotating at correct speed and you will have the same symptoms as if alternator was failing. Had this scenario on another car.