Tapping the Dash Lights Circuit

So I'm finally getting around to hooking up the illumination right now. I'm using posi-taps to splice into the rear diff switch. I tapped into the black for illumination ground and the black/white for illumination power. When I turn on my lights to illumate all my switches my garage door switch lights for a split second then goes out? Any ideas?

 

So it seems like the red/white wire is illumination. I hooked it up to that wire and it works, now I just need to figure out which one is illumination ground, it's not the black one.

 

Got it working right. Red/white was illumination power and the Black/white was illumination ground.

 

Congrats, so you've got dimming and switch function now? All switch leds have an associated resistor that prevents over current and being diodes aren't harmed by reverse polarity so it's sometimes just a matter of seeing what works. Toyota doesn't seem to follow any standard color scheme and changes colors on a whim. On mine green is illumination power and green/white illumination ground. Even your aftermarket garage switch doesn't use the same colors as ch4x4 save for black being illumination ground.

 

Yup dimming works. The harness coming off the garage switch isn't from CH4x4. I bought a garage switch off ebay for $6 that came from China that stopped working correctly right after I hooked it up, I would have to push it 3-4 times for it to work. So I didn't bother hooking up the illumination. I finally got a new garage switch from CH4x4 that matches the light blue factory leds but kept the old harness since it was already soldered to my garage opener.

 

The ebay and Amazon switches still have the same internal layout as ch4x4 and use the same connector plug, they just don't color code the wires the same as ch4x4 but should still be a simple swap. They're 5-pin connectors that don't use the center pin. I crunched one of mine by accident and opened it up to see how to change led color and intensity. Pretty simple stuff.

 

I used an add a fuse on the TAIL FUSE and the lights on my switches come on when I turn the lights on

 

Lots of ways to illuminate switches but this thread is specifically about tapping the dash circuit to keep Oem dimming on all switches. If you want yours to dim as well connect the switch ground to illumination ground, not the same as chassis ground as our trucks use a variable relative ground to achieve dimming. Every switch and panel that dims will have a dimmer ground wire. I accessed the circuit at the ac controls plug using the nite-eyze instructions since my two switch panels are below it.

 

Thank you for this info. It helped me wire the way I really wanted to. FYI on the 2018 Tacoma, the pins you reference above are correct, but the negative wire is tan in color.

I used a T tap with two wire slots, and a inexpensive blue backlight LED push switch that has two bulbs: one for the writing wired to dash lights, and the other bulb lights up when the LED bar is turned on.

 

Which switch panel did you use to get the 4 switches in?

 

I got it off ebay. $20 even included 4 switches.

https://www.ebay.com/itm/223565258843

 

So reading thru this, for the CH4x4 4-wire switches.....if I wanted to be able to dim the switch lights I tap red 2 to the green wire illumination (+) and the ground to the green w/ white wire as an illumination (-). If I didn’t care about the dimming capability I could run the illumination (+) to a add-a-fuse plugged into something like the taillight fuse to power the lights (so I could more easily reverse the switches if I wanted).

 

I know this is an old thread but Hoping you could help me out. I am trying to wire a illuminated switch for some heated seats. The heated seats came with a wiring harness that only has a positive for the switch illumination. The harness has a combined ground for the switch and the heating units. Based in your post here I’m assuming there is no way to wire the switch illumination to dim since the switch grounds are combined. Is this correct?

 

Let’s see the back of the switch you have. Perhaps you can splice the ground wire (attached to the switch) out and run it to a variable ground that allows you to dim. You’d just put a cap on your bare end.

 

here it is. There are 6 wires coming out of the switch. I’m not 100% sure what each one is. This harness is for a hi/low seat heater switch and it has 2 relays per seat which I thought was kinda strange.

 

Unless you have the pin map you’ll need to see where those two black wires run.

 

Yeah that's what I figured. I don't have a pin map (the kit doesn't really even have instructions).

I hooked up the switch to the panel circuit to test the brightness of the illumination and its noticeably brighter. Do you know of any way to make it dimmer possibly by adding a resistor inline?

 

Good ol solder and some very small resistors. You can try some of those load resistors but again you’d need something super small.

If you’ve got the time you can cut the wire harness up and see where those black wires out of the connector run. One will probably be going directly to a ground and I’d guess that’s for the illumination. Hard to tell.

 

I’ve opened up every switch I’ve purchased plus a few of the oem switches and from what I’ve seen “impossible” is a relative term and depends on how much you want it. I installed the Besond seat heaters and swapped both color and resistance values as well as scraping the inside of the wheel so the white “level bar” gets illuminated. If you were willing to pull the white connector and open up the switch housing(every one I’ve seen so far just snaps together) and post a pick of the circuit board that has he switch and leds we can show you where to cut a trace and solder in an additional ground wire to connect to the variable ground that provides dimming. Usually there’s a resistor for each led that controls maximum brightness and even if you don’t add the wire you can change resistors to more closely match your oem switches.

 

I will see if I can get it apart and shoot you a picture. Thanks in advanced for your help!