Greetings, car is a 92 Lexus LS400 So after a while of not constantly driving (2 months) I now have my car not shift out of 2nd gear when the car is on drive WHILE the headlights are on. Never heard of this, saw in another forum that one solution was cleaning battery terminals and making sure everything was tight. So I did, cleaned everything and same problem persists. Never had this issue before when I used to daily and no harness seems damaged. Battery voltage and alternator voltage were checked and are fine, car and tranny drives great again only happens while headlights are on... any help would be greatly appreciated!

 

Do you know about the infamous trunk wiring problems?
It might not be your issue but you should give it some thought/exploration. It can cause more symptoms than shown in this link -> http://www.lexls.com/tutorials/lighting/bulbout.html

 

was your ECU ever reworked for the leaking capacitors?

https://www.clublexus.com/forums/ls4...capacitor.html