Replacing headlight switch

[Nubie4Runner]

So after experiencing problems with headlights coming on their own, dash lights that wont turn off and hi-beams that behaved strange I searched around here and found that problem is likely the headlight combo switch. I had the dealer do a diagnostic and they came to the same result.
My question is can anybody point me to a DIY replacement as the dealer has quoted over 330$ to fix. Seems like it would be easy but I`ve had no luck finding any pointers on replacing this switch. Any help would be greatly appreciated!

 

[Acidmeld]

I think there are only 2-3 screws holding the steering column covers on and another 2 holding the stalk on. Not difficult at all.
Just be careful with the wires in that area and do NOT disconnect the yellow connector.

 

[Nubie4Runner]

I tried removing the column housing by removing the 2 screws that are behind the steering wheel (have to turn the wheel to expose them) and then removed the 1 screw on the lower housing and it didn't seem to want to come apart. I didn't use any force or pry at all as I expected it to separate pretty easy. Do I just need to use a little force to get this housing apart? I've seen alot of info out there about removing the wheel and such but also seen this fixed very easy on other models by doing as you suggest. For sure I will be removing the neg battery, last thing I need is airbag deploying.

 

[Acidmeld]

A little tug should pull it apart...

 

[Nubie4Runner]

So the exact problem still exists after replacing the combo switch!
Interestingly I had to drive like 5 hours to get a replacement for 50$ and when I got home what'd ya know everything works fine! After seeing everything was normal I didn't bother replacing the switch until today when I come home and see the Headlights on again! So I swapped switches and found no change whatsoever. This issue happened today when the weather has warmed up and it's raining instead of the deep freeze and snow we've had for awhile. This wet weather has definitely somthing to do with this issue. So once again my T4R has to sit with the neg battery cable disconnected. The symptoms are 1) Wet weather 2) In OFF position, the Headlight relay makes loud buzz when turning on the high beams - it does not do this when in ON position 3) Dash/stereo lights stay on but go out when turning on hi beams??? So i'll be going back to dealer as this was their solution and I would have been out 400$ with the same problem after. So I'm thinking a ground issue and heard of 3 prime ground points to the frame and block. Can anyone shed some light on these locations so I can check. Also any suggestions what might be the culprit would be awesome.

 

[Nubie4Runner]

Just an update that dealership found the fuse block (inside/drivers side) is badly corroded/mouldy on the back. Makes sense cause I can see the silicone job the previous owner did on the windshield. So looks like water was is getting in, though I've never seen any water whatsoever at the feet. This problem occurs when it rains. 500$ they quoted for the new fuse block and all the connectors! Luckily I have access to another one and will just cut the wires and splice it in.

 

[Nubie4Runner]

My issue was a fuse box molex connector that had 3 bad/corroded wires. All is good after fixing, saved hundreds!!
Since I have a spare switch I thought I'd share a way to test it and check for fault before replacing. Pictured is pin layout and expected continuity of a working combo switch.

 

[JP_SanDiego]

I'm having a similar issue. Where exactly is this part located? Thanks