Time to ask for some help

So I swapped my headlights a couple months ago at first I used the ballast from my old headlights which worked with the exception of the high beams and it would tell me headlight malfunction.

But I bought the correct ballast brand new from bell Lexus and when I installed them the error lights all went away buttttt now I can’t turn my headlights off at all, the only time they turn off is when the cars off and the high beams don’t work still

I’m thinking maybe I have to reprogram the car to accept the new ballast or maybe I need new wiring but I’ve been told the wiring should be the same

Lmk what y’all think, I’ve been to lazy to really look into it and I’ve been driving the car like this for a couple months

 

This will require very specific knowledge likely with use of a wiring schematic. Sorry I won't be able to help much but from what I've gathered, Lexus doesn't use programmable modules like you get with BMW and most euro cars. On those cars you can "program" in features as all their models are pre-wired for all features when they leave the factory. From what I understand Lexus has various wiring setups that are optional depending on features. I could be wrong about that but this is my first thought. Maybe you can subscribe to that repair manual service for $10 for one month i think it is and you can compare pinouts/wiring of cars w/ and w/o triple beam? Seems you're 95% of the way there.

I am guessing it's possible the ballast and headlight switch aren't communicating when you try to turn off the headlights or turn off the high beams. So you may have to focus on those two pinouts and see exactly how they control the respective functions. It's probably incredibly simple to fix but I'm guessing it's just a matter of knowing where and what to fix. I wish I knew more but I haven't really messed around with lexus cars on that level. I used to do quite a bit of programming of BMW cars though and it was pretty complex back in the early days to do that. iirc i think a hex editor was needed to do some mods. lol

By the way the pic you posted looks nice from that view. Reminds me of the new Silverado color scheme (which I like) where the face is black. Anyway hope you get it fixed!

 

The wiring between the car and headlights is the same...the difference between the single and triple beams headlights is internal to the headlights.
Having said that, the Main Body ECU is what really controls the headlights.
I've attached the wiring diagram so you can see, but really there isn't anything you can do with the wiring.
The Main Body ECU (people call it the MPX) controls the Drivers headlight, and in turn the Drivers headlight controls the Passengers headlight.

It I had to take a guess, the Main Body ECU is probably different in vehicles with the Single beam vs Triple Beam headlight.
Maybe the parts department at the dealer may be willing to look it up and let you know.
In terms of programming the Main Body ECU, that's not something that can be done...at least not at the dealer level.
You have to assume that somewhere someone has the equipment to do it, but that's going to be like trying to find the last Unicorn.
If it's just a matter of swapping the Body ECUs, that's likely the easiest way to go.

 

you pull out the V6 and drop a V8 in the engine bay? Looks good 👍

 

side note, car looks amazing.. side mirror caps actually work on this set up IMO

 

Did you ever solve this issue? I’m currently having the same issue with the headlights on my 2017 IS300.

 

hey did you ever figure this issue out yourself? my girlfriends 2017 is having the issue of passenger headlight staying on all the time unless the car is off completely