I am in the process of installing ditch lights on my 2017 SR5 and also got one of the OEM-type switch buttons. I believe I understand the connections for the green, black & red1 wires of the switch to the ditch light harness, but the splicing/tapping of the “Red 2” (second red wire next to the black wire) that is used to illuminate the switch backlight of the ditch light button has me perplexed.

I’ve searched the internet, but the videos & discussions I’ve found seem to describe connecting the switch buttons without showing it. I’ve located the wiper heater “Green” wire that I think others describe tapping to, but this line has already be tapped for a light bar switch by the installer of the light bar (not installed by me).

My questions are:

(1) Can I tap the ditch light “Red2” wire to the “Red2” wire of the light bar switch that taps to the “green” wire of the wiper heater button?

(2) If I can do (1), can I solder to the same tap spot that “Red2” of the light bar switch taps to the “green” wire of the wiper button? Or, should I tap “Red2” of the ditch light switch to the “Red2” of the light bar switch?

(3) If I cannot/should not tap to the same “green” wire of the wiper button, what is my alternative (possibly the “green” of the AC adapter button)?

(This project has reinforced my belief that if you want something done right, do it yourself. And, has me tempted to undo what was done by others, and re-do it myself!)

Thanks in advance for the advice!

Not sure how it is for the 5th gens, but I tapped into my seat heater control fuse. Since I have an SR5 with no seat heaters.

You need a test light. You should be able to find what you need at the fuse panel. I found an unused fuse spot for my 4th gen.