not sure what is going on with my truck. I had it out last weekend and the 4wd worked like a champ. Light comes on and even tried the elocker and works. This past weekend, i was out in the middle of no where and decided to take the truck down an easy down the hill, into the creek, and up the hill. I would say even a stock trd taco would make it. so i went out to turn the hubs to lock and went backinside, put the 2hi to 4hi and pursued down the hill. I noticed that the 4wd LED wasn't on but didn't think much of it as sometimes it takes a few rotations to turn on. Then i passed the creek and started up hill. well at the very start of the incline the truck stopped. i was . so i backed up a bit and tried again, the rear tires just kept on spinning. so i went to check it out, it dug itself in. I had my pops drive and was taking a look. Some reason the front wheels weren't grabbing/moving/rotating. my dad then said, u sure ur 4wd is working. i put the stick back into neutral and selected 2hi and then back to 4hi then 4lo. same thing just kept spiinning the rears. man i was in trouble. i lucked out and winched myself out but still, there is something wrong with the 4wd. I need some assistance to get it resolved.
1) where could i check first: I've checked the 4wd fuse and it is good still.
2) where is the 4wd ecu and how could i test to ensure its working?
3) any assistance would be great!!! since i've the slightest idea to as where to start looking (acutally i was thinking it is the clutch?)

specs of the truck:
99 taco v6 manual tranny, trd elocker in rear, manual hubs in front,
lifted, 33s, otherwise stock.

 

make sure ur vaccum lines are in good shape

 

where does the vacuum lines connect to? the Tcase or tranny?

 

Welcome to YotaTech.... there should be a vaccum line down near the front diff

 

thanks for the info elton... i will check it out. would that also attribute to the 4wd lights not comming on in the dash?

 

it might or the bulb burnt out

 

I had the same issue on my 4Runner. Here is my thread from a little while ago.

https://www.yotatech.com/forums/f2/actuator-4wd-my-4wd-wont-engage-91288/

Key points were:

1) Check vacuum lines and the check valve (see thread above)
2) The 4WD dash light is real. It comes on when the actuator is engaged--If it comes on, you're actually in 4WD. If not, you're definately NOT in 4WD.

Also, did you try going in reverse and then trying to engage in 4WD again?

 

ok i figured it out. i was a loose hose. i replace the hose with a new one and works like a champ. it was hard to see at first but with more looking and fiddling around with teh hoses, this one came loose easily. thanks for all hte info team. w/o you guys i would have spent endless $$$ at the dealer. you have saved me!!!!

 

I have looked through countless 4WD threads but I need to clarify something. Most threads are from people with pushbutton 4WD (I have the small shifter on the floor next to the AT shifter on my 99 Runner SR5). I shift into 4WD and get nothing...where should I begin? Are there vacuum lines to first check with my setup? If so where are they (by the front transfer case???)? Any direction would be great!

 

yes you must check the vacuum lines first! then make sure the actuators are working.

the vacuum lines connect to the front differential. the push button has nothing to do with this. it is the same on both (generally speaking for what needs to be known for this thread)

 

I ended up having the dealer look at it when I had my rig in for some other maintenance and he said it was the actuator that was stuck. They got me going again for no additional charge. You were right Seanz0rz!