Got a 2000 4 Runner. Had the tranny replaced last September, and have never tried to engage the 4WD since that time.
When I shift the 4WD lever to 4-Hi, the green light on the dash no longer comes on.
I briefly tried to check things out the other day by raising all four corners of the rig and putting it in 4WD. The 4WD engages fine, but the green light still doesn't come on.

Any ideas?

 

bulb burned out.

 

verified bulb is OK. Any other ideas?? Also checked wiring harness continuity...

I did notice that when they replaced the transmission, they didn't hook up the hose going from the base of the transfer case shifter to the transmission... I'm guessing it's some sort of vent hose????
Anybody else seen that hose before??

 

4wd is vacuum activated (some bits are anyway) I am unsure of exactly
which...but that may be a vacuum line required for proper 4wd operation

 

If you do have 4WD, but no light, your problem is either the bulb, the sender switch on the front diff, or the 4WD computer. Odds on bet is the sender switch. Pull it and check for continuity when operated.

On the hose, I think you are talking about a breather that vents up by the shift levers.

 

OK, I just got the "vent" hose back in place, and took it for a drive, and lo and behold... the 4X4 light works...
Could this be some vacuum source, as Big Balls McFalls suggested? I will take a pic of the hose this weekend so you can see the shape of the hose, as it is a preformed hose.