DIY: Gen 2 Illuminated 4wd switch

[maverick491]

From the day I bought my truck it bothered me that the 4wd switch didn’t illuminate and as I was browsing through TRDparts4you.com I saw that they had a “kit” to illuminate the 4wd switch. They also had a link to someone's install instructions, but I thought they could be clearer, so I decided to document the project as I did it and write it up myself.

DISCLAIMER: I am not responsible for any damage to you or your truck if you attempt this mod.

BE ADVISED, THIS IS NOT A PLUG AND PLAY INSTALL, IT REQUIRES YOU TO CUT AND SPLICE INTO YOUR FACTORY HARNESS, AND IT REQUIRES SOLDERING.

If you are not comfortable with any of that then I suggest that you not attempt this mod.

Tools Required.

Very small flat blade Jewler’s screwdrivers
Needle nose pliers
Soldering iron
Solder
Electrical tape
Heat shrink tubing
Lighter
Wire cutters
Wire strippers
Two small gauge electrical butt connectors

OK, if you’re still reading then here’s what you will need to order. Illuminated 4x4 Dial/Switch fits 2005+ Tacoma 4x4

This kit includes a current model 4-runner 4wd switch, part number 84724-35020 and two terminal leads part number 82998-12420

Step 1: You will need to take the two terminal leads and extend the wires on them. Strip back the insulation on the end of the terminal leads, and then solder about 2 feet of speaker wire to each lead. (You won’t need all two feet, but speaker wire is cheap, and it makes fishing it through the dash a little bit easier.) Then heat shrink it all up. I did not document this part because it is kind of difficult to solder and take pictures at the same time. See photo of finished patch harness.


Step 2: Take the parts out of the 4-runner switch that you will need. First remove the bulb from the 4-runner switch and set it aside as you will be using this later. It is what is a bayonet type bulb so just unscrew it about a quarter turn and it will drop out.


* Next take note of the 3 tabs around the outside of the back side of the switch.


Take a small flat blade jewler’s screwdriver, and gently ( I EMPHASIZE GENTLY! IT IS THIN PLASTIC) pry the back up at the tabs.

Repeat this for the other two tabs.

Then remove the back of the switch, and set it aside. Be carefull as there is a spring inside the switch that may try to escape when you remove the back.


Continued in next post...

[maverick491]

Continued from previous post...

Step3: Now you can see the light diffuser. This is the other part we need from the 4-runner switch. Grab the light diffuser with a set of needle nose pliers and just pull straight out. It is not glued or melted in. It will come out with just a little bit of effort, just make sure to pull straight out so that you don't bend the mounting posts.


Now you can put the back back on the 4-runner switch, and set it asside. You should now have a bulb and a light diffuser sitting there.


This concludes the work that you can do inside. Grab your completed patch harness, your bulb, and your diffuser and head out to your truck.

Step 4: Now we're going to take the 4wd switch out of the Tacoma. Grab the 4wd switch knob with your fingers and pull straight out.


Step 5: You will see the opening where the light diffuser will be shortly. Grab this opening with your needle nose pliers, and pull straight out from the dash.


Step 6: Un-plug the harness from the back of the switch.


Continued in next post...

[maverick491]

Continued from previous post...

Step 7: Remove the “blank bulb” from the back of the switch the same way you removed the real bulb from the 4-runner switch.


Step 8: The Tacoma switch has four plastic tabs holding the back of the switch in place instead of the three that secured the 4-runner switch back.


* Remove all these the same way you did on the 4-runner switch. Again be careful as this is thin plastic and this is the switch that you actually care about.


Step 9: Note the arrows in the above photo. They are the mounting holes for the light diffuser. Now you can insert the light diffuser, it will only fit in one way, and you’ll see that the posts on the diffuser line up with holes in the switch housing. Press it in securely. See the diffuser in place in the next photo.


Step 10: Now replace the back on the switch housing, making sure that the internals of the switch including the spring are back where they came from. You’ll see that the light bulb socket lines up with the bulb crater in the diffuser. Install the bulb from the 4-runner switch.


That’s it for the switch re-assembly, set it aside and move on to the wiring.

Continued in next post...

[maverick491]

Continued from previous post...

Step 11: Remove the outer knobs from the H.V.A.C. controls, and remove the H.V.A.C. unit by grabbing the posts with your needle nose pliers and pulling toward you the same way you did with the 4wd switch. Just remember to pull from both sides or you could take a chance on snapping the clips if you pull at too great of an angle.


Step 12: Remove the two wiring plugs from the back of the control unit, and set the control unit aside. Sorry I could not photograph this part but it was hard to hold the H.V.A.C. controls, unplug the harness, and take a picture.

Step 13: You are going to want to fish the harness you made earlier from the 4wd switch location down to the H.V.A.C location, with the terminal leads up at the 4wd switch location. Again, hard to photograph and do at the same time, but if you hold the terminals end up at the 4wd switch location and start feeding the other end into the dash, you should be able to feel it as it reaches the H.V.A.C. location. Then just pull the un-finished ends out.

Step 14: Back up at the plug for the 4wd switch. Take your small screwdriver and pry up the white cover from the black plug.


* Alternate sides that you are prying on, and the white cover will come all the way off.


Step 15: Now that the white cover is off you can see insert the terminal leads into the plug. I am pretty sure that they will only go in one way, but regardless you want all five slots to look the same when you are done. You can see what I am trying to say more clearly in the picture.


Snap the white cover back on and you are done with this part. See the picture of the completed plug.


Continued in next post...

[maverick491]

Continued from previous post...

Step 16: Lets return to the H.V.A.C. plugs that we talked about a little while ago. You are concerned with the 12 pin plug. That is the one on the right as you are looking at them. It is all smaller gauge wire as compared to the other plug.


* You are going to tap into pins 3 and 8. They are numbered on the plug, but it is very hard to read, so I have marked them with arrows in the above photo.

Step 17: Here is where it may get a little scarry for some of you. Take your wire cutters and cut the wire going into pin 3. Leave about two inches of wire coming out of the plug. Strip 3/8ths of an inch of insulation from both ends of the wire you just cut, and from one of the wires in your patch harness. Insert all three pieces of wire into a small gauge crimp connector and crimp the hell out of it. Repeat this process for pin 8. In the end it should look something like this. Again, the wires in question have been marked with arrows.


(Note: I attempted to solder the patch harness to the leads on the H.V.A.C. plug as was described in the other write up I read, but the solder did not seem to hold reliably to the leads, so I opted for this method)

Step 18: Make sure that you electrical tape or heat shrink up your new connections, and tape the harness back into a nice neat bundle.

Step 19: Plug the 4wd switch back into it's harness, and turn on your lights.

(Note: Nothing I could find on the subject made it seem to matter which of the new wires was connected to pin 3 and which was connected to pin 8. Mine lit up on the first attempt, so either I was lucky, or it really doesn't matter. If your light does not work, try switching the leads up at the 4wd plug by removing the white cover again and pulling your patch harness out and reversing it.)

Step 20: Plug the 4wd switch back into the dash. Re-install the plugs into your H.V.A.C. control unit, and re-install that in the dash, and replace all the knobs that you previously removed.

You should now have a nicely lit 4wd switch that is still controlled by the pannel dimmer and is color matched to the rest of the lights.


I know the picture is crappy. I'll try to take my tripod out tonight and take better picture if I have time.

One last note: The bulb from the 4-runner switch is a smaller bulb than the surrounding bulbs, so it does appear a little dimmer than the other controls. If you noticed the 4wd bulb has a little orange rubber cover on it. I tried it, that cover will fit over the bulbs from the H.V.A.C. cluster and still fit in the 4wd switch. That would make everything be the same brightness. However, I am not sure if the little orange rubber thing could withstand the heat of the bigger bulb, or if the diffuser that toyota used in the 4-runner switch could withstand the extra heat also. I am content with it as it is for now, though I may try a bigger bulb later.

[nd]

Great write up Maverick! I am personally not anywhere near comfortable enough to try that on my truck but definately appreciate the time and effort you took to get all those pics and do the detailed write up. I'll let you do it for me next time you make your way down to SC

[maverick491]

Originally Posted by ndcouch

Great write up Maverick! I am personally not anywhere near comfortable enough to try that on my truck but definately appreciate the time and effort you took to get all those pics and do the detailed write up. I'll let you do it for me next time you make your way down to SC

Thanks!

Ok, sounds like I plan. Order up the parts and have them wating for me at the Carolina meet. Just make sure I do it before we start drinking for the day as soldering is one of the few things that I do better sober.

[nd]

Awesome!

[nd]

How long did it take you to do this?

[007Tacoma]

Great write-up! Nice detail and everything. I would do this on my truck, but I can't seem to find the 4WD switch.

[maverick491]

Originally Posted by ndcouch

How long did it take you to do this?

I worked on it before work on Sunday and then again after I got home from work on Sunday, so all total probably 4 hours counting the taking of the pictures and taking notes on what I was doing. Figure probably an hour and half to do it again since I wouldn't be doccumenting it all the second time.

Originally Posted by 007Tacoma

Great write-up! Nice detail and everything. I would do this on my truck, but I can't seem to find the 4WD switch.

007, we can do this to your truck at the Carolina meet too if you manage to make it to it. In addition to the parts mentined in the kit, you will also need a Tacoma 4wd switch as well.

I'll install the switch and even make it light up, now as for making the switch actually do anything.... Well that's a different story...

[Jeff]

Outstanding job, Mav, great job with the pic's also. Sure wish I could make that Carolina meet. When is that, anyhow?

Jeff
06, V6, SR5, 6spd, Brilliant Red.

[apexbill]

I just lit mine up! It took about 60 minutes; (5 minutes to take the switch out of the truck; 10 to take a part both switches and move diffuser and bulb and reassemble; 10 minutes to build wiring harness and heat shrink the whole thing up; 30 minutes to splice into the hvac harness; 5 minutes to reassemble everything and test. Worked the first time though it is too light during the day to see it without taking the dial off of the switch to see the diffuser.
I will check it out again tonight - can't wait!!!


I have also installed lights under my hood with a pin switch. I will take pictures and post. I used some nice LED's encased in aluminum bodies and mounted one on each side. I have also put LED light strips under both sides from VMInnovations.

More pictures to come!!!

[Banchi94]

Originally Posted by apexbill

I have also installed lights under my hood with a pin switch. I will take pictures and post. I used some nice LED's encased in aluminum bodies and mounted one on each side. I have also put LED light strips under both sides from VMInnovations.

Hey apex, I'd like to see some pics and a write up on this, if possible. I really want to gets some lights under the hood, too, and your idea sounds very intriguing.

Thanks!