Solved - 4hi Light blinking, won't "disengage" 4hi and 4low work fine

Well, I've searched and searched, and can't seem to find anyone who's had my exact issue.

I just bought a 2000 Tundra Limited 4x4 with the 4.7L WITH ABS, and it's having 4WD issues. Like the title says, my 4hi light is blinking constantly even though I feel a small clunk when it disengages, and can feel that the front wheels aren't being powered, but the light blinks anyway. I can get into 4hi and 4low just fine, the light just won't quit flashing when I try to go into 2wd mode. It is an ABS truck, but that light is NOT on, so to my knowledge that system is working correctly.

Any leads? I'm going to try unplugging the battery for a while just to see what that does. I'm not super familiar with how these systems work.

Clarification: I have tried going into neutral while driving, engaged/disengaging while moving, while moving in reverse, stopped and in park, stopped and in neutral, stopped and in drive, stopped and in reverse, and nothing has worked.

 

Welcome, throw up some pics?
If never heard of that problem though

 

Thanks! I bought it last night and don't have any decent pictures in the day time. I'll do that soon!

 

I have had that happen. Stop, put truck in neutral, and wait a minute. that should fix it. i have also had to put my truck in reverse too.

 

I should've clarified. I have tried going into neutral while driving, engaged/disengaging while moving, while moving in reverse, stopped and in park, stopped and in neutral, stopped and in drive, stopped and in reverse, and nothing has worked.

 

It may be a bad position switch on the transfer case

 

how would I go about testing that?

 

I’ve had mine do it as well. The way I get it to stop flashing is by making a turn. It’s like it didn’t fully disengage until I made a somewhat sharp turn.

 

I don't really know, you may want to watch YouTube on it, I think it's a somewhat common problem so someone has had to make a vid on it sometime

 

Bad switch/actuator? Let us know if the battery reset trick works.

 

Sounds like you tried everything but if you stop, put it in neutral, then switch to 4 low, wait 'til flashing stops, switch back to 4 high, start driving in a straight line and switch to 2wd.

 

Will do, thanks.

I’ll give that a go. Thanks!

 

May auto locking hubs are not disengaging, but power is? Just thinking out of the box

 

Or the opposite?

 

"I then poured the rusty,dirty, water like substance in the actuator onto myself as I opened the case."

sound like me but with gas when I did my fuel filter!

 

This actuator repair thing (per the above link) sounds like it goes easy or is very complicated and is not to be attemped unless you have the time to go the entire distance.

Takeaway from the stories of all the commentors is to make sure your breather lines are connected to prevent the problem!

 

Thanks! that helps a lot. The truck is currently at my parents house (dad's got the tools) and it'll be a few days before I get time to head over there. I'll keep everyone updated.

 

Can’t say for sure but I bet it’s dirt in the actuator. I’m 99% sure it’s not in the abs because I’ve removed all of that stuff on mine and the transfer case shifts just fine.

 

So I was messing around with it tonight, and it engages and disengages 4x4. you can hear the motor turn and the clunk of the actuator as it shifts from 4x4 to 2x4. I'm going to be it's the actuator sensor thingy. I pulled the plastic cover revealing a spiral gear and a big plastic gear, and it was perfectly clean inside. forgot to take a picture though.

 

I haven't researched your particular setup but my 2001 4runner had the same issue a few years back. There were two switches on the transfer case, one to tell it when it was in 2wd and one to tell it when it was in 4wd. If one switch sticks the warning light will flash because it doesn't know if it is in 2 or 4 or both at the same time. In my case it was the forward switch sticking causing the truck to still think it was in 4wd. Thus the confused flashing light. The part was about $90 at Toyota. It looks to be a $30 switch to me.

If you pull the wire off the front switch I bet the light will go out when you are in 2wd. Of course the trucks are different so the switches could be reversed. Easy enough to try especially if you have enough ground clearance to get under easily.

 

Thank you! That’s a huge help!

 

Throw up some pics of your truck?

 

here ya go! I also started a built thread here. https://www.tundras.com/threads/the-1100-tundra-build.32740/

 

Well, I made a boo boo. I unplugged the 4lo sensor instead of the 4hi sensor, and now it’s stuck in 4lo with the 4hi and 4lo lights flashing. What now? The sensor is plugged back in, but it won’t do anything.

 

I know it’s simple but did you try disconnecting the battery for a few minutes?

 

That’s what I’m about to try. I can’t think of anything else.

 

Maybe unplug the 4hi sensor too? Can’t mess it up anymore now.

 

I unplugged the battery for 15 minutes, and it changed nothing. drove it up nd dow the driveway, still nothing. unplugged the sensor again, nothing.

It's completely stuck in 4low, and it won't do anything. is there a way to reset the 4x4 controller or something.