Lexus LX Undervoltage Issue

Oh, that sounds familiar! I had a similar problem with my old BMW 3 Series. Different car, I know, but the symptoms were almost identical: lights dimming, weird electrical glitches popping up all over the place, and struggling to start. Did you check the battery terminals for corrosion? Or maybe tried measuring the voltage while the engine is running to see if the alternator is actually charging?

Thanks for the insight. Regarding your suggestions, what voltage readings should I look for while the engine is running to confirm proper alternator function? What's normal, and what indicates a problem?

Okay, so when my BMW was having issues, a mechanic friend told me that with the engine running, you should be seeing somewhere around 13.5 to 14.5 volts at the battery. Anything lower, and your alternator probably isn't keeping up. Honestly, though, unless you're really comfortable with electrical stuff, I'd suggest getting it checked out by a professional. Could save you a headache, and maybe prevent further damage!

I appreciate the advice. I took it to a qualified technician. The battery was heavily discharged and defective. Replacement and labor cost 290€. Thanks for pointing me in the right direction.