cant get the diff's to lock

[elmariachi]

Before you get too involved with the wiring, I suggest putting it on a lift or jackstands and try to lock them in the air...Yours is probably just sticky from lack of use...

I think he is predisposed that there is a problem, so....get some .

 

[Tools R Us]

I think the relays are ok though they were my concern initially since I cant hear them click. (see next paragraph)
...

Now that you have been close to the box, do the relays click when the switch is turned on? It's very rare for the box to go bad, most of the time it's the actuator.

Check, RF(#6) to GND(#13), 11.9v


I'm not sure what "open" means, but this is what happens w/ CDL light on and RR and RR FR on the dial.

R3(#16) to GND(#13), 0v
R4(#14) to GND(#13), 0v

R3(#16) to R4(#14), 0v
R4(#14) to R3(#16), 0v

IG(#8) to R3(#16), 0v
IG(#8) to R4(#14), 0v

RF(#6) to R3(#16), 0v
RF(#6) to R4(#14), 0v
...

Open means no connection. The relays are on double switched circuits, ie the power is switched by the locker switch and comes into the box on term #6, the ground side is switched by the actuator, comes in on #14/#16.

There are a couple of ways to test the ground side. The most common is to set your meter to ohms and check between ground and the term, open should read infinity and closed, close to 0. Another way is set the meter to DCV, hook the positive lead to power and the negative to the term, when open it should read 0v when closed ~12v.

The motor runs one way to lock and the other to unlock, the relays reverse the polarity to switch motor direction. You can confirm on the rear, by hooking the meter to the #1 & #3 terms, when the locker is operated you should see + ~12v one way and - ~12v the other as the motor runs.

The motor only runs a few seconds, as it turns the gear with the slider/limit switches, it comes to the open spot, disconnecting the ground side, turning off the relay/motor. The slider/limit switches control the position, timing of the actuator. So yes you can run the motor, but if it's run for too long or in the wrong direction it can move outside of the limit switched area and the actuator will need to be taken apart and retimed.

It sounds like you have a problem in the actuator, a search will net some threads on referbing them, but be aware that Toyota considers them sealed units and does not service any parts inside of them. So if anything other than brushes or the bearing is bad, or you break a part you will be looking for a new/used assembly and IIRC they aren't cheap!

 

[MR.SIGINT]

First off, don't test it on pavement. Second, if they haven't been frequently used, they will often be hard to lock. They need exercise before assesing that you have a problem. Find some hills (any of those in Cali??), twist the knob and climb. Toyota will do the rest.

x2. I was having the same problem for a couple months. Put a CDL switch in, hit a hill for a few minutes and everything started working.

 

[bpenn1980]

Before you get too involved with the wiring, I suggest putting it on a lift or jackstands and try to lock them in the air...

Sometimes there needs to be a large difference in wheel rotation for them to engage, so while idling in Drive in the air, just slow one wheel down by hand and it should lock

There are times when mine will lock instantly and others when they will only lock after a few sharp turns in the muck...

They have never failed to engage when I needed them though

Some lockers (non-OEM) require more than a full wheel rotation difference before the lockers will engage


Yours is probably just sticky from lack of use...

I would agree, but even when I couldnt get my rear to engage I could still hear the click from the control box and the actuator motor engage. Neither of those are happening when turning the dial to FR.

I think he is predisposed that there is a problem, so....get some .

Cant get to the hills until next weekend, but I spent a good hour in a dirt lot driving around looking like an idiot to all the neighbors. Rear locking up perfectly now, so thats good.

And yes, I do believe there is a problem. When I fix it I'll post it up.

Now that you have been close to the box, do the relays click when the switch is turned on? It's very rare for the box to go bad, most of the time it's the actuator.

Nope, no click at all for FR RR. Nice loud click from the box for RR and motor sound from under the car.

Open means no connection. The relays are on double switched circuits, ie the power is switched by the locker switch and comes into the box on term #6, the ground side is switched by the actuator, comes in on #14/#16.

There are a couple of ways to test the ground side. The most common is to set your meter to ohms and check between ground and the term, open should read infinity and closed, close to 0. Another way is set the meter to DCV, hook the positive lead to power and the negative to the term, when open it should read 0v when closed ~12v.

I'll do this tonight before I test the motor.

The motor runs one way to lock and the other to unlock, the relays reverse the polarity to switch motor direction. You can confirm on the rear, by hooking the meter to the #1 & #3 terms, when the locker is operated you should see + ~12v one way and - ~12v the other as the motor runs.

Yep, I'm seeing this with the rear but not the front.(see below) I'm going to touch a 9v battery to the front M3(+) to M4(-) for a second and see if I hear the motor. If I still dont hear the motor then I guess its is 100% the actuator &/or limit switch.

--" Rear test:
(this is my base since the rear works and I can hear the motor when I turn the dial)

Idea is that when the dial is turned from OFF to RR (for the rear) the M1(#3) to M2(#1) will spike to 10-14.5v (mine spikes to 10+v). Then turning the dial from RR to OFF should spike the M2(#1) to M1(#3) connection will spike to 10-14.5v (mine spikes to 8+v). Though the M2 to M1 voltage is low, I hear the motor during both tests.

Front test:
Turn the dial from RR to FR RR should spike the M3(#7) to M4(#5) to 10-14.5v (mine is 0v). Then going the other way from FR RR to RR should spike M4(#5) to M3(#7) to 10-14.5v (again, 0v)."--

It sounds like you have a problem in the actuator, a search will net some threads on referbing them, but be aware that Toyota considers them sealed units and does not service any parts inside of them. So if anything other than brushes or the bearing is bad, or you break a part you will be looking for a new/used assembly and IIRC they aren't cheap!

I've got all these threads bookmarked and ready to go if need be. I'll be under there this weekend for the birf job, so it'd be relatively easy to test the limit switch and clean up the actuator if needed. Plus, I have the FSM so I can do the timing correctly.

Thanks for all the insight!

 

[Tools R Us]

First off, don't test it on pavement.

Why not? Other than being slightly more difficult to get to lock/unlock, I see zero reason and test mine on dry asphalt before most wheeling trips.

 

[elmariachi]

Why not? Other than being slightly more difficult to get to lock/unlock, I see zero reason and test mine on dry asphalt before most wheeling trips.

When you turn a locked axle on pavement, something has to give. Hopefully its the tires. But if the tire sticks just right...snap. Its an unneeded stress on axle components and has been known to result in damage. Ask me how I know.....

 

[Tools R Us]

When you turn a locked axle on pavement, something has to give.

Yes, the tire(s) slide.

Hopefully its the tires. But if the tire sticks just right...snap. Its an unneeded stress on axle components and has been known to result in damage.

Your saying that the axle/locker components are so frail that they are prone to breakage from light throttle testing in a parking lot? My experience has been somewhat different, locked climbs, on rock, etc. I will bet the traction is better on Moab rock than most parking lots, combine that with the throttle needed to clear some obstacles, making for orders of magnitude higher stress. If my junk is so worn that it going to break from a simple parking lot test, I would prefer that it broke there, rather than on the trail when I'm counting on it!

Ask me how I know.....

You have broken axle/locker parts in a parking lot?

 

[bpenn1980]

While in there for the front axle job this weekend, I casually noticed NO wires going to the front diff actuator. Its missing the entire set of wires!

Anyone ever see this before? I bummed out.

Though if I turned the dial and just drove around the hills I'm sure the problem would have corrected itself....

 

[elmariachi]

Yes, the tire(s) slide.

Not always. It depends on the tires and the pavement.

Your saying that the axle/locker components are so frail that they are prone to breakage from light throttle testing in a parking lot?

Yes, that's what I am saying.

If my junk is so worn that it going to break from a simple parking lot test, I would prefer that it broke there, rather than on the trail when I'm counting on it! You have broken axle/locker parts in a parking lot?

Yes, I sat in the passenger seat while a dumbass business partner of mine, with the axles locked, grenaded a birfield on a 1997 80 Series, one-owner, mall Cruiser with 61k miles in a dry parking lot in Del Norte, Colorado. That's all I need to not test my lockers on dry pavement. YMMV.

Its missing the entire set of wires! Though if I turned the dial and just drove around the hills I'm sure the problem would have corrected itself....

And you ran all those voltmeter tests before looking to see if the wiring was in place?

 

[98 SNAKE EATER]

And you ran all those voltmeter tests before looking to see if the wiring was in place?

 

[bpenn1980]

And you ran all those voltmeter tests before looking to see if the wiring was in place?

You read the entire thread, you should remember that I did crawl under there 1st. With the dust cover off it was much easier to get a view and I had another cruiser to compare it with on hand.

Thanks for chiming in, its been a pleasure.

 

[elmariachi]

You read the entire thread, you should remember that I did crawl under there 1st. With the dust cover off it was much easier to get a view and I had another cruiser to compare it with on hand.

Thanks for chiming in, its been a pleasure.

No holiday sense of humor? Sorry if I stepped on your toes or offended you. This ain't the place to be too sensitive.

 

[Red Beard]

I don't know why yota changed the FZJ lockers from the FJ's version. My FJ80 CDL works fine, and locks everything at once.

 

[elmariachi]

I don't know why yota changed the FZJ lockers from the FJ's version. My FJ80 CDL works fine, and locks everything at once.

Do you have a center diff lock or locking front and rear axles?

 

[bpenn1980]

No holiday sense of humor? Sorry if I stepped on your toes or offended you. This ain't the place to be too sensitive.

My bad, still getting used to the Mud use of haha

Its not you, I'm a little stressed with the holidays and what not. Sorry for sounding off a little

Take care man and happy holidays

 

[Red Beard]

Do you have a center diff lock or locking front and rear axles?

Factory CDL Switch.

 

[elmariachi]

My bad, still getting used to the Mud use of haha Its not you, I'm a little stressed with the holidays and what not.

Well, I was jacking with you a bit. I thought it humorous that a guy in the heart of LA was trying to get his lockers to work. Living in Houston, I know what its like to live two hours from dirt.

I know this truck is stressing you out. You'll work through it all and be happy when you finally hit the trail.

Happy Holidays to you and yours from me and mine. .

 

[elmariachi]

Factory CDL Switch.

His front axle will not lock. Your CDL is something entirely different.

 

[Beowulf]

While in there for the front axle job this weekend, I casually noticed NO wires going to the front diff actuator. Its missing the entire set of wires! Anyone ever see this before? I bummed out.

I remember one other member that found the front diff lock harness was completely missing after he purchased the vehicle used. I am guessing some original owners got the option but didn't need or want it and accidentally locked the front on pavement and found they couldn't unlock them and they couldn't steer the vehicle. That would be pretty scary for someone that had no idea what was about to happen (beginning driver, loan the truck to a friend, soccer mom, clueless dad, or whatever.)

Probably took it back to the dealer and said "take it OUT!"

-B-

 

[bpenn1980]

Well, I was jacking with you a bit. I thought it humorous that a guy in the heart of LA was trying to get his lockers to work. Living in Houston, I know what its like to live two hours from dirt.

Thats very true. I had to hunt all over the place to find enough dirt to exercise them on without driving more than 45 minutes...ridiculous. Sometime this city slicker life hurts

I remember one other member that found the front diff lock harness was completely missing after he purchased the vehicle used. I am guessing some original owners got the option but didn't need or want it and accidentally locked the front on pavement and found they couldn't unlock them and they couldn't steer the vehicle. That would be pretty scary for someone that had no idea what was about to happen (beginning driver, loan the truck to a friend, soccer mom, clueless dad, or whatever.)

Probably took it back to the dealer and said "take it OUT!"

-B-

I bet thats what happened. Makes sense. Hopefully a new harness will give me a "plug n' play" front locker!