UPDATE - Problem fixed.

First I want say thank for those who responded. So, it took me a few hours but I finally fixed. Below are the steps I performed:

1. Top off or change all fluids
2. Test out both solenoid was active and not leaking (Good)
3. Test out vacuum holes are not leaking, blow into the ones going down to ADD to listen to see if the ADD is engaging and disengaging. (good)
4. Test SW on ADD, it did not have continuity for the full range in pressing down on the switch. Cleaned and it work perfect. reconnected (Fixed Problem)

When for a test drive pressed down on the 4WD switch, engaged with fine click, drove for awhile, was afraid to disengage 4WD, when I finally did it was SUPER SUPER silent, didn't even hear a click. I through 4WD didn't work at all so I tested it 10 more times and could fell the extra torque on the engine when engaged. It was so smooth and quite that this was the only way I can tell.

I hope this helps and give back to this forum. Feel free to IM me if you need help. I learned so much from this, I believe I understand the system more than an average SEARS mechanics now (but that doesn't say much).

 

Cleaning the position switches and ensuring continuity through the ENTIRE throw of the plunger is key.

 

Used this info to fix 2001 that refused to shift out of 4wd and was stuck with blinking lights.

This thread can be confusing since the 01-02 runners are different than the previous 3rd gens.

My solution: I pulled both my 27 mm switches from the back of the transfer case. When I checked them with a multi-meter they completed the circuit when closed. I thought this wasn’t the problem but I sprayed them with contact cleaner and exercised them. I also sprayed the 6 pin connector. Changed front/rear diff and transfer case fluids since they were due anyway.

Fired up the truck and light gone and in 2wd. Test drove and everything was quick and centerlocker and lo all worked.

My advice if you have an 01-02 that is in limbo with the blinking light pull the two switches, clean with contact cleaner and hopefully you will have the good result that I had.

Thanks to all the previous posters, good luck.

 

Check the actuator's. There's one by the transfer case and one under left hub by the differential. There's little sensors for the 4x4 to function properly. It's likely to be the one by transfer case.

 

I have a 1999 3rd Gen 4WD and had to take apart the transfer case Actuator. There was fluid in it when I disassembled it and would like to know what type of oil goes back in.

Is it a special gear oil?

There was also grease on the prongs for the actuator....I assume normal dielectric grease will work?

 

*********************************************
There should be no oil in the actuator. if there is Transfer gear oil in it than something is leaking. The tracks are probably be greased with some type of lithium grease.

 

Looking for a definitive answer on the timing for the REAR 4WD transfer case actuator timing gear. 1999 4runner limited 3.4 V6.

My transfer case actuator is now working after cleaning it out….I am reinstalling the gear for the actuator motor and have seen a lot of conflicting Information about the position. Also need to know if the transfer case should be shifted into 2 or 4WD.

thanks.

 

will you please email them to johnpisan@gmail.com?

 

I'm back!

I'm trading my 72 Chevy Cheyenne K10 4x4 that needs the body work finished on it (which I don't have the time or resources to finish), for a lifted 97 4Runner SR5 4x4 with a great 3.4 and 5 speed. I'll be on this forum a lot more from now on

I already have to finish my 72 Monte Carlo getting it painted soon, and then I can get the interior in it and start driving it once in a while.

 

I just want to thank everyone in this thread! I have been lurking and trying to figure out why my 99' limited was stuck in 4wd. Mechanic quoted $2900 to fix the transfer case actuator. Due to you guys, I bought a multi-meter and tested both sensors on the transfer case, and finally the A.D.D sensor. The A.D.D sensor tested faulty, ordered a new one for $66 dollars shipped, two days later my puppy is switching 4hi, 4lo, and all wheel drive! Thank you guys a million!

 

99 limited with j shift m/m how to access the three top switch on t-case ? should i buy all three switch prior to getting there since it seems like a big job , and witch switch are right

 

​​​​​​​Since it's a PITA to get to those t-case switches, it would be a good idea to just change them all. Test the old ones and save any that test fine.

 

I've worked my way through this entire thread, and learned a lot and have still not yet quite fixed my '96 Surf's 4WD. For those interested in the progress so far, I've posted it on this thread: https://www.yotatech.com/forums/f2/u.../#post52484449

I've also copied out and tidied 10 pages of notes from this thread and a few other sites, summarising different people's issues and the corresponding fixes and diagrams. I'm not a mechanic by any stretch of imagination, so please accept a layperson's effort. Hopefully they are archive-worthy.

 

Hey Guys,

So i started to follow this thread after being unable to switch into 4wd drive. When i would hit the button, the light would flash but nothing would happen. Then the light started to flash even when i hadn't pressed the button (and then sometimes it would randomly turn off, only to turn back on later). It seemed like the problem started when i was driving through some heavy snow/slush. I first started by changing out all the sensors (yes...all 6 of them). To my surprise, the issue was not fixed. Then my buddy jumped the actuator and the actuator would manually go into and out of 4wd mode.

We then looked at the actual 4wd button to see if it had continuity....that worked fine.

To make a long story short, the problem ended up being that water had gotten into the 4wd actuator and corroded everything pretty badly. The connectors were almost completely covered in corrosion. We cleaned up all the corrosion, relubricated everything, and the 4wd now works perfectly...

Just wanted to add my solution to this thread...in case anyone is having a similar issue....

2000 4runner Limited

 

That very closely matches the start of my problems: there is a small rubber breather pipe on the side of the transfer case actuator that can easily be pulled off by vegetation or other obstacles. Water got in, and started to get intermittent failures. Cleaning it helped, but then my front actuator went down due to a hole in the rubber vacuum diaphragm. Still trying to get the whole system going again, but both actuators work after an extensive clean-up and relubrication of the TC actuator.

I covered this in the summary doc above^

 

I uploaded the images in the first post to help users be able to download use them in their diagnosis of fixing their 4wd issues.

 

Just got myself a 1999 Limited 4WD and the light wouldn't turn on so I was ready to rip out the cluster to put in some new bulbs. Thankfully I checked the fuses and saw it was missing the 20A fuse for 4WD (person who sold it to me 1000% did this on purpose) once I replaced it the light instantly turned on and started blinking nonstop. I had checked under the car a couple days ago and saw that the front drive shaft was engaged and spinning and the 4WD button wouldn't make a clicking noise or anything. I was definitely stressed out thinking it would be a much more expensive fix so thank god I stumbled on this blessed thread. Anyways point is, we out here in 2023 and this thread is still a lifesaver!!! Going to swap out both switches tomorrow and hopefully my issue gets resolved. Thanks again my man

 

If you find one of the switches on the transfer case is at fault, I still have a brand new sealed in the bag for sale.

 

I haven't been able to get under the car and check it out but based on all the people who had the same issue as me I'm feeling pretty confident that it would be the switch. Is it OEM and how much would you sell it for? Also, by any chance do you have pictures of where I should look under the car or anything, I'm not mechanically inclined and don't really know where to start.

 

It is a factory OEM Toyota new in bag transfer case switch - 84222-35110 Transfer indicator Switch. $55 + shipping

It is the switch with a wire pigtail that is on the transfer case.

The switch I have is the same switch for the center diff lock, L4 position, neutral position switch on the t-case.