Center Diff Lock not working. Any ideas?

[NewportSun]

So heres my problem. When i push the button to lock my center diff, nothing happens. No lights come on my dash, nothing happens at all. Isnt the VSC off light supposed to come on or something along those lines? I not sure what the issue is. Any ideas would be great. Thanks.

 

[ebg18t]

Is 4wd properly engaged?

 

[NewportSun]

Yes its the all time 4WD model

 

[Erich_121]

have you checked the switch??

 

[ebg18t]

Are you trying to engage it in gear or in neutral? Also does it work in 4low vs 4hi?

 

[xxaarraa]

have you checked the switch??

+1 on checking the switch. Drop the plastic panel and check the connections for the switch.

 

[mad4run]

could be a problem with the shift actuator (the electric motor/gear box that converts between 4hi/lo and diff lock/unlock)

It is the black box in the center under the car, I have been messing with mine for a few weeks now, I know the gear timing for the differential but I am having trouble with the 4hi/lo as I bought the car without knowing it didn't work...
It is pretty simple but the dealership/mechanics will tell you not to mess with it.

Has it ever worked?
You can try to unplug the cable that connects to the actuator then plug it back in, (will not hurt your car, just simple things to try)

If you are into working on this yourself send me a message and I will tell you about what I have learned through a lot of trial and error

 

[4RBob]

for me, it was the 4WD control module (white box located behind the glove compartment). it had collected some moisture and corroded. part was a few hundred dollars, i think.

 

[4thYota]

Help

Any one figure this out? 2004 V8 4runner with same issue. Center diff and 4Low won't engage. No blinking lights like everyone else. No noises nothing. Checked both dash switches and they both are good. Would surely appreciate someone pointing me in the right direction. And where's my manners. Brand newb here. This is my third 4runner plus I've had 2 4x4 pickups. Gleaned a ton of info from this forum over the years and hadnt joined. This one has driven me to ask for help. Thanks

 

[wtadeo]

Hey guys,
I recently bought a 2006 sport edition 4x4. So I noticed that the center diff doesn’t work in 4hi and 4low. I pressed the RSCA just for fun and the center diff engages and the vsc turns off. I then popped the cover off below the center lock button and noticed that the center lock switch was unplugged. I plugged it in and still doesn’t work from that lock button. I’m wondering, is the center lock supposed to automatically engage when you press the RSCA button?
Thanks in advance

 

[BlackWorksInc]

You can try having someone get under the vehicle with a dead blow or a hammer and firmly tapping the actuator assembly (not too hard, we're not trying to break the damn thing!) while you shift the vehicle through 4WD and engage the Center Diff Lock.

Another thing you can try is engage the center diff lock and to drive the vehicle forward 10ft, shift to reverse and drive 10ft, and shift back and drive forward 10ft.

These are usually the ways I'll try to free up a stuck actuator. The main reason this happens is because people don't regularly exercise their 4WD system (I think Toyota says in the manual to engage it like once a month or every other month?).

If that doesn't work, then you're going to want to go into diagnostic mode and start checking the electrical circuits to determine if the actuator assembly needs to be replaced (the more common failure, though as pointed out above a 4WD ECU is a possibility also.)

 

[rwh963]

i have a 2007 v6 4wd. one owner vehicle. the center diff. has NEVER been engaged! i use hi 4wd as needed. i've tested the lo 4wd (not recently, but not too long ago either), and it engaged. is it too risky to test the center lock at this point? don't want to disable the drive train.

 

[BlackWorksInc]

i have a 2007 v6 4wd. one owner vehicle. the center diff. has NEVER been engaged! i use hi 4wd as needed. i've tested the lo 4wd (not recently, but not too long ago either), and it engaged. is it too risky to test the center lock at this point? don't want to disable the drive train.

I mean it's very unlikely that it'd get stuck in center diff lock, it is possible I suppose.

That being said exercising the 4WD system regularly is good prevention from having to tear the case apart to replace the actuator.

The actuator is literally a bunch of plastic gear reductions to move one-two steel rods in the transfer case and between the plastic of the gears and the I assume lithium (it's a white grease but I never bothered to really analyze it) they get sticky/crusty and that usually makes the actuator sticky/sluggish.