Rubicon? The lockers are wired so they cannot be engaged except in 4Lo.

 

Yes. In 4wd low. Key on, engine not running, and in first gear with TC in 4L. I am able to press switch down 2x, get steady lights on both front and back. Verified front is locked in. Rear is not locked in even though I am getting a steady light. Putting back in 2h, and removing key, gets me a slow blinking rear indicator light. rolling jeep foward or back, will turn light off. Roll it back- light comes back on. Driving in 2h, get an erratic blinking of rear indicator light.

 

Something else, the lockers need differentiation between the L/R sides to reliably lock up. Driving straight will often not be enough to get them to lock.

 

Yep, had noticed other comments where guys had to turn a bit to get the light steady. My issues are the rear indicator light is on steady, yet it is not locked in. And, if left in just the right spot, the rear indicator light will blink with key out of ignition and back in 2h- its like the system still thinks its getting the activate locker signal.
With the steady light, I tested and got continuity in the locker indicator switch that lies in the rear diff.

Just thought of something else: I did the rear brakes last night, and noticed that the pass side drive axle was replaced. What concerned me at the time, was that the studs were 1/4" shorter than the other side. Replaced those. BUT is there anyway an incorrect axle could be causing the switch to think its locked in, but not really? I think I read the DS and PS are not the same length. If the previous owner screwed it up, could that do it?

 

It is impossible to to get the axle shafts reversed and complete the installation. FYI, the shorter shaft is on the driver's side... same as the front axle.

That the light goes from flashing when first actuated to steady should indicate that axle is locked. What makes you think it is not locked?

 

Because I put one wheel in the air, engine off, key on, rear locker lit, in first gear, and the diff is open- tire spins,

Pulled cover off, and found that the lock plate, was somewhat cockeyed, and every time the edge that is off to the left passed the sensor switch, it activated the light. I flushed everything out best I could with brake cleaner, and blew it out with compressed air. Checked pressure on hose inside the diff, and found it to be 5.5 psi. Had helper work switch with cover off, and could see bellows try to push plate to left, but it never seemed like it was all the way. Put cover back on, filled with lube and test drove. Plate must not have released quite perfectly, because at slow speed, the locker light would flicker- up to about 15 mph. Once I got it up to speed, it stopped, but as I slowed down, either engine brake or coasting, it would flicker again.

So- lock plate is not doing what its suppose to. Bellows seems to be intact with correct air pressure. Never seems to lock in- I can def feel the front when it does, and I confirmed differential is open by jacking it up and watching other wheel spin backwards when rear locker light is engaged. This tells me that the plate has moved enough to the left to pull the plunger on the sensor switch, but not enough to actually do anything.

So- now what? the carrier/locker assembly is cooked? Try flushing fluid and see if it clears itself? pull carrier and tear it down for a thorough cleaning? I did not see anywhere in FSM that addresses that. Any comments from anybody who has done it would be greatly appreciated!

 

Does the locker's air compressor shut off a few seconds after it comes on and does it stay off as it should after you turn the locker switch on?

 

Yep about 2 seconds. when I had cover off, I put a vacuum/pressure gauge on end of hose in diff, and got 5.5 psi. Watched it for 15 min and compressor did not come back on. It seems like the bellows does not have enough oomf to push the plate squarely, or there is something in there that is preventing it from moving as it should. Looks like you have to press off/on bearings to get the bellows off? Would a guy need to reset backlash if that was the case?

 

The Rubicon locker switch is only able to be engaged in 4 Low from the factory, but it is easy to modify the wiring in the dash behind the switch to make them able to engage in any t-case position or speed. That may have been done - pull the dash and look to see if any of the wires are spliced together at the back of that switch to be able to tell. When I bought my rubicon 2 years ago, I found a previous owner had done that to mine.

 

I guess that must depend on what differential you have then.

Stock TJ Rubicon locker.
Funny thing was, after I installed the shafts and got everything all buttoned up, I realized I didn't check the new shaft lengths against the old ones before I installed them.
That being said, everything I have ever read about them always said you couldn't put the long side in the short side so I assumed I got lucky and had them installed correctly so didn't bother pulling them back out to check.