2018 LED headlight conversion, then CATASROPHIC electrical failure

i replaced my 2008 sequoia stock headlights with the 2018 sequoia LEDs and harness. Its been about 3 months and everything was fine.
Now suddenly i have had a catastrophic electrical failure. windows, AC, moonroof, automatic shifter lock, outside air temp, all not working, ABS and traction control dash lights fail.
The dealer checked everything, tore apart the dash and changed the alternator but they cant find any issues.
Has anyone else had an issue with the 2018 LED conversion?
We dont know if that is it, but wanted to check it others had issues after the swap.
Thanks

 

Haha gotta love dealers…

Did they run a health check with Techstream? Any codes? Did you check all the fuses?

 

Dumb question but I subscribe to the KISS method…..did they check the battery?

 

I feel like that’s enough time for those to be unrelated.

I can tell you I have seen lots of weird electrical problems created by bad grounds.

 

I really hope you disconnected the battery before you did any type of electrical swap.... I would probably start looking at the wire that goes through the fire wall, as it may be damaged or exposed and causing a short. I say this, because I pulled my headlights out due to an accident, expecting a total loss, but I got it repaired and returned, but I did notice the exposure on the wire. I heat shrinked it and added some electrical tape it for extra protection... If you cut any wires, I'd suggest you reinspect them for damage.

This thread sounds familiar though tbh...

 

hi, thanks for the input and ideas. They found the issue this morning.
there were 2 wires in the telescoping steering column that had become worn, and were randomly shorting out when the steering wheel was telescoping at start up.
they couldn't determine why the issue started, but the fixed it and tested it all out.
Im glad it wasnt the headlight conversion, because i love it...thanks

 

Glad they got it figured out.

 

And you still had to pay for the alternator replacement?

 

Would you expect any less?

 

The sequoia headlight conversion looks very good , is there a way to still get the harness?

 

There is a whole thread on it. Here you go.
2018 Sequoia LED Headlight Harness For 2nd Gen Tundras | Page 31 | Toyota Tundra Forum