2018 Tundra LED headlight wiring info with diagrams

Thanks for the quick reply bro. Mine is a 1794 model, do I still need to switch them? Since @thomasbus337 only included the signal/parking light adapters for the non Platinum/1794 models. I assumed I did not have to do this on mine. Can you confirm @thomasbus337?

 

Yes you have to but you only have 2 wires in that 3 pin connector you have the parking light purple wire already in your DRLs you only have to move your ground to pin 1 as you can see in the diagram we have the ground in pin 2 mine is a 16 Pro so should be the same in yours

 

Thanks iHacker. I should have read through all the posts in this thread. Now it's clear that there lies the issue. @thomasbus337 even posted a pic of it in post #42 I will do that first thing in the AM. Thanks again to both of you!

 

@eledobleu does the DRL dim when the lights are on normally on 2018 OEM? Is that the factory way?

 

Haha, you're out of luck Pal!!!! But @BlueBottle just posted a video for you!!!!


But here are some pics for motivation!!

 

I have not installed his harness on my 17 platinum yet but I was under the impression that the pin out change was only required on models other than the 1974 and Platinum edition. @thomasbus337 could you please comment on that?

 

lol Looks awesome.

 

The pins still need to be swapped on the platinum/1794 for the ground.

 

At @thomasbus337 or anyone that can help.. just got done with my harness. Does this look right for my platinum guys? Wanna make sure before I intstall. Can’t wait!

 

Looks 100% correct from here.

 

All models will have to move the ground pin for the directional to function properly. If you don't switch the pins you'll still have a turn signal but it will be dim and hyperflash because the stock wiring will be illuminating the 8w "parking light" 7444NA filament and not pulling the 28w signal.

However if you are running VLEDS V3 or V6 units you can avoid this because you will be able to fit the V3 or V6 LED bulb into the new 2018 housings while still using your stock bulb sockets outside of the headlight unit

 

At thomasbus337 thank you!

 

Sure enough it functions as it should after switching the ground. Now onto the next issue... the DRL stays dim when you turn on parking lights only. Can someone confirm if this is the OEM functionality because I could swear in 'parking light' mode, the DRLs were bright before.

Switch Status | DRL Function
Off | Off
Parking Light |Dim
Headlights | Dim
Auto (during day) | Bright

 

The factory function for the drl’s are bright during the day and switch to dim at night “parking light” mode

What probably confused you is some people were wiring them on bright all the time

 

Okay then I might have killed something when I did not switch the ground wires because at full daylight, in parking light mode, it was still dim. I'll start by checking the fuses.

 

Did you do the 1 relay for the red wire on the drl’s.

 

Looks good, but don't forget the cavity plugs into the unused pins to avoid any water getting into the connector

 

Can you be more specific @inferno_pro_satx. Thank you for your help btw. I followed the connection diagram provided by @thomasbus337

 

How do you have the drl LED’s wired “ the red & purple wire at the 8 pin connector”?

 

Sorry I should have mentioned that the harness was purchased from the OP. I'm almost certain it's not the harness though because no one else has reported this issue. I might have messed something up. I'll check the fuses in the morning.

 

Did you run 1 wire inside to the drl control unit and wire up a 4 pin relay?

 

Negative. The harness was pretty much PnP except for having to switch the ground on the turn signal plug.

 

Cyrus has a 1794 so he already has the factory DRL wiring. I can't answer the dimming question on a factory setup because I have an SR5.

 

@Cyrus If the engine is not running and/or the parking brake is engaged, and you turn on the parking light, t will stay dim. Once you start the engine and disengage the parking brake it goes on full brightness.

Check my video, it shows it.
https://www.youtube.com/watch?v=qDl7nbjPNXA&feature=youtu.be

 

@ 53 seconds is when I disengaged the parking brake

 

@thomasbus337...thank you almost forgot about the cavity plug..forgot to order the cavity plug for the high beam connector. Try to order some on Amazon but won’t be here till Monday.Does anyone in cali know where I can go buy some? Can’t wait any longer lol

 

Man can it be that simple?!!! I had never paid attention to the DRL functionality that closely. I will test and report back.

 

Please test and report now I’m curious as well

 

I guess if you were in a hurry you could dab a little bit of silicone sealant in the unused spots to seal them off.

 

YOU ARE THE MAN @BlueBottle!!! I had never paid that much attention to the functionality of the DRLs and sure enough, I've always used the handbrake when I park the car. As soon as I disengage the handbrake it brightens. You just saved me hours of troubleshooting a non-issue. I owe you a beer man!