Been having electrical issues with my 1995 Lexus ls400. First started when I was getting a high pitch whine from the alternator. Had that tested they said alternator bad needs replaced. Had the alternator and battery both bought new. The voltage is good now but having a issue still with the lights on dash flickering every now and then seems to happen more when it rains leaning towards a short what do you guys think?

 

yes, short or bad ground somewhere is most likely, and since the stock LS400 wiring and electrical system is perhaps the most reliable system ever put into a vehicle, the place to start searching for the problem is in the wiring where any aftermarket crap has been installed.

examples would be: aftermarket sound system, amps, subs, etc. or HID headlights, or aftermarket alarm/security systems or remote start systems, and other add-ons - in my experience, this add-on stuff and the associated questionable electronics installers make up most all of the weird electrical issues that happen on the LS400

PS - LS400's NipponDenso alternators are extremely reliable, so you very likely have leaking power steering fluid that has killed the alternator or else the faulty aftermarket wiring mentioned above, and either one of those will kill the new alternator in time as well.

 

The car is all original one owner never been in a wreck and he was a lawyer and used it for traveling highway miles. The previous owner never had anything major go out but he did mention having to replace a battery every 3 years which hinted to me something wrong electrical. After a year of me having it the voltage regulator started going out so went ahead and replaced the whole alternator cause its was the original factory installed alternator. When the alternator was taken out inspected for leaks around PS and any fluid coming from lines,unit,etc... no leaks. Trying to keep the Lexus original and not alter anything. One issue i am leaning towards is I have a crack on the right headlight plastic one and it is getting water bad in it could this be causing the electrical shorting? Also what would be good to seal the crack till I can get a replacement part for it?

 

what is the mileage on this car?

 

silicone can be a decent ghetto-rig seal for a cracket headlight. Fix that then trace for electrical shorts.

 

150k miles on it