Rear Locker

[Blue Phoenix]

Before anyone flames, I checked in the FAQ and used the Search to try and help me with this, but I saw nothing like what led to my rear locker locking and not disengaging. Heres the story:

Shortly after leaving for a camping trip up 24 through Manitou Springs (those of you who have driven it know its about a 6% grade), I pushed the POWER button with Overdrive turned off, and I see my Rear Locker indicator light come on. No flashing like usual, it just came on and stayed on.
I stopped to check it out and could find nothing wrong in my ignorance, and kept driving on since it wasnt behaving as if it was locked. I know I know, not a good idea.

Now before anyone starts thinking I snapped or broke something, I am sorry to disappoint, but nothing broken.

We kept driving and I noticed that when I accelerated hard (around 3K RPM) uphill, it would start flickering, not blinking, flickering and would sort of go dim.

Later on, on the trail, I really wanted to see what was going on so I did some tight turns, and yes it was for sure locked and showing no intention of trying to unlock.

My front locker works fine and when engaging both, the rear goes dim while the front is locking and then lights up.

This continued on our way home, with the flickering uphill and turning off briefly, and then coming on again and staying on.

Does ANYBODY know whats going on and how I should trouble shoot this. I have the day off tomorrow and I see myself trying to get to the root of this.

Again, soory this is so long and thank you in advance for all the help. Pictures would be helpful in any info you guys may give too.
I kept dr

[-Spike-]

Some very odd behavior here. Does your truck normally engage the rear locker when you push the 'power' (I assume thats the button on the center console, not on the dash) button?

-Spike

[Blue Phoenix]

Never, all its suppoed to do is remap the engine for shifts at higher RPMs and quicker shifts. Maybe this is a feature no one knew about?

[-Spike-]

I doubt that. Sounds like you have a short somewhere. Driving with the rear locker engaged wouldn't bother me, but having it lock in that manner would force me to check it out immediately.

-Spike

[Blue Phoenix]

Either that or I hit the actuator or something around it when I removed the rest of my exhaust pipe?

[-Spike-]

Why would it engage when you hit the 'power' button? The two systems should be completely independant.

-Spike

[-Spike-]

Did you remove/break any ground wires?

-Spike

[Blue Phoenix]

I glanced, but havent gone in depth. The exhaust routes next to the actuator I think and MAYBE I hit it. But like you said, two completely different systems. I'll be spending some quality time under her tomorrow, so hopefully I'll find some indicator of what's wrong. Honestly, though, I dont know what I am looking for.

[Beowulf]

Originally Posted by Blue Phoenix

Honestly, though, I dont know what I am looking for.

Simple, you are looking for a wiring problem with the rear actuator. You didn't say one way or the other but I am guessing the rear locker light did not go off when you turned off the "Power" button, correct? Otherwise, you would have turned it off and left it off for the drive home.

Driving in a straight line with the rear locked isn't terrible but you will not be a happy camper around town and getting into tight parking places. There is a procedure to use a 9v battery and unlock the actuator if you cannot find the wiring problem fairly quickly. I don't have it handy but search for 9v and actuator or locker (80-section only) and you should turn it up. (You will have to use 9V* in the search)

Since you were working in the area of the rear actuator and not in the dash then I would start there though the logical place would be under the center console area where the POWER button is located.

-B-

[Blue Phoenix]

The two systems are stand alone though, correct? I quickly turned off the POWER button after it indicated the locker was engaged, but even after turning it on and off and trying everything I knew how to do, nothing worked. I will look into the 9V, but is that just a quick fix? I just really hate shops and hope this doesnt lead me to them.

[-Spike-]

Doesn't suprise me at all that the locker didn't disengage when you turned off the 'power' button. The locker circuit involves an ECU and multiple contacts and electrical paths in the actuator itself. When power is applied to the actuator to engage the locker, it turns a motor which loads a spring which moves the arm that locks the diff. When the motor turns to a certain point, a contact is made that tells the ECU that the spring is loaded- and then the ECU shuts off the power to the motor. Another contact is made when the arm actually moves, which tells the ECU to turn the indicator light 'solid'. To disengage, the ECU sends power on a different wire to reverse the motor, unload the spring, and allow the arm to move back to its unlocked position. Without power to that wire, the locker will never disengage.
So, somehow you had power on the wire that actuated the locker, or you had some weird ground situation that caused the locker to engage. I would expect that if there wasn't still power to that wire, turning the locker switch on and off would unlock the locker, but anything's possible since we don't know where the power came from to lock it in the first place. It might be that the power is still applied- which would be bad, and is why I'd figure it out before driving the vehicle, or even leaving the key on.

Just to scare you a little more, your locker is probably not fully engaged, as evidenced by the flickering dash light. The actuator arm is probably not quite in the right place to indicate 'locked'. I'd not like to find out what happens when it engages or disengages under power on pavement in a turn. Probably could get ugly.

-Spike

[-Spike-]

Another possible scenario is that the locker actuation was not caused by a short, but rather by a hard shift, or by nothing at all. That would indicate a problem with the spring/arm in the actuator itself. Maybe it's just floating around, and it was a coincidence that the dash indicator came on when you hit the 'power' button.

-Spike

[Blue Phoenix]

HAHAHA....Yeah as soon as it happened my 80s life flashed before my eyes. I figure this is going to take more than tomorrow to figure out. My biggest fear is that it is in limbo between being fully engaged and not, so, we'll see what happens. I am planning on disassembling the entire actuator unit tomorrow. UGH.

[Blue Phoenix]

Does anyone have a link or an actual picture of the actuator unit? Also, where should I follow along the wires to see if I have a good ground and no other issues? My FSM should have come in the mail by now, and not a day too late, so I'll see what I can find in that.

[tblume]

PM sent..

[Beowulf]

Originally Posted by Blue Phoenix

I am planning on disassembling the entire actuator unit tomorrow. UGH.

Start simple! Check the wiring!

There are posts here in the 80-Section containing the schematics of the diff lock system. This is in the EWD which will not be part of the FSM unless you also purchased that manual. (You should) There is also a section in the NCF that discusses the theory of operation of the diff-lock system.

-B-

[Blue Phoenix]

I'll start with the wiring....What areas do I need to look at?
Sorry...My mechanical know how is stuck in the engine bay.

[Beowulf]

Originally Posted by Blue Phoenix

The two systems are stand alone though, correct? I will look into the 9V, but is that just a quick fix?

The transmission "Pwr" switch/system and the diff-lock switch/system are not related though it is possible they may share something in the EWD. I wouldn't think so but it is possible. tblume will take care of you there.

The 9v "fix" is to get your rear actuator unlocked. It is a quick fix so you can drive around town and work on getting the problem diagnosed and fixed.

-B-

[tblume]

a thought here; could the actuator be gummed up keeping the splines engaged and the light is lit (sometimes, almost) showing the motor trying once in a while at 12V? if so 9V will prolly not help. I popped the cap of my rear actuator and it was really easy; can manually moving the linkage in there while a helper rolls the wheels around pop it loose? I'm thinking a bit more oomph than the spring can give might be the ticket.


thanks Beowulf for the .pdf last month, it's making it's rounds and helping us new guys more than once, you're the man.

[Blue Phoenix]

Thanks to all of you guys...Beowulf has got the ticket. Right now all I am concerned about is getting it out of the rest of the linkage to prevent any damage as this is my DD. One thing I thought of too, could this at all be related to Diff lube, or the lack thereof? It wont hurt to change it. Thanks again

[Romer]

Take a look at this thread. Post #5 tells you how to disengage wiith a screw driver while you figure it out.

http://forum.ih8mud.com/80-series-te...ed-locker.html

Probably some mechanics hanging around at the ralley

BTW, you can do Red Cone with an Open 80

[Blue Phoenix]

So, tools needed:
ME, the biggest tool
9v and 12v (just in case) Batteries
Ohm meter?
and I guess regular hand tools from what Ive read.

Sorry for being so needy, I just dont like stopping midway realizing I have to go to the Auto shop to pick something up.

[Blue Phoenix]

Thanks for the boost of confidence on Red Cone Romer, I was waiting for a comment from you on this. I'll be using every bit of info thats thrown at me.

I should have mentioned before, this happened on a trip to Kenosha Pass area- did Georgia Pass and Glacier Ridge side trails along with Middle Fork Swan River and Webster Pass if my memory serves me right. Fun trip and thank goodness nothing broke!

[Romer]

Sarahs Truck had a different problem where the locker would engage ok, but then would not dis-engage until it was driven on for a while. We took it apart back in camp and the spring and actuator where installed incorrectly.

Have you tried engage and disengae with the locker switch and have someone stand there to see if they hear anything?

Id get it unlocked and take your time isolating the problem

[Blue Phoenix]

I stood outside the truck myself, had my wife engage both and then disengage: I clearly heard the front locker disengage. I heard a click from the rear as if it was trying to disengage, but it wasnt the "normal" clink that it makes. So Im thinking a sticky actuator.

[Blue Phoenix]

PS- love the Avatar Romer.

[Romer]

Originally Posted by Blue Phoenix

I stood outside the truck myself, had my wife engage both and then disengage: I clearly heard the front locker disengage. I heard a click from the rear as if it was trying to disengage, but it wasnt the "normal" clink that it makes. So Im thinking a sticky actuator.

I would take the actuator off, dis-engage the locker and then photograph the actuator taking pictures as you disassemble and clean. Sarah's all had lost the O ring so it was pretty dirty where the spring was and it was the spring that was installed backwards.

Spring went the other way, cleaned surface with an emory cloth and used black FPIG in place of an O -ring putting it back together. Robbie diagnosed and gave instructions

Originally Posted by Blue Phoenix

PS- love the Avatar Romer.

Thanks - Big Sluice on the Rubicon