Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › Lexus SC400 charging system issue › Lexus SC400 charging system issue September 23, 2014 at 2:49 pm #622694 TomParticipant I’m not entirely certain that voltage is a problem. Under full load, at idle, most alternators can’t keep up. If the voltage is back up to 14.3 at 2k RPM, I’m not sure there is anything wrong there.