Help Needed - R Diff Lock Indicator Switch

I’m supposed to go camping tomorrow... any help is appreciated.

My rear locker light was blinking intermittently during everyday 2wd driving. I had a look at the rear diff thinking maybe it was the actuator and noticed that the locker indicator switch was broken off. I ordered a new one (84222-0K010) and the replacement seemed straightforward.

Now the rear diff is locked in 2wd and making a squeaking noise. I removed the sensor and everything is fine. Replace the sensor and it’s locked in 2wd and squeaking again.

What’s the trick to replacing this thing correctly?

 

Just to be clear, this isn’t the diff lock switch in the cab on the ceiling. This is a sensor on the rear differential.

 

You are in new territory as I have yet to hear of this issue. First things first. Is the diff *actually* locked as in you know it to be mechanically true? Is the "squeaking" tire chirping indicating it's locked? What's the state of the indicator light? What are your DTC's with the sensor installed if there is one?

My first guess taking a shot at it if indeed the diff is locked and the indicator light isn't lit with no trouble codes is that the sensor is over inserted causing the plunger to engage the dog clutch. This is a far fetched idea and should not happen.

The second item that jumps out is why did your original indicator switch break off? I feel like whatever caused that may be the key to the root of the problem.

 

Crazy off the wall guess on my part but maybe the battery has to be disconnected during the replacement.

 

Yes, definitely.

Off.

No idea, don’t have a reader.

I’ll check the old sensor to see if I missed a spacer. The sensor has a o-ring, so no gasket.

Looks like the guard was pushed into the sensor and broke the plastic top off. Maybe a rock?

Maybe crazy enough to work! I’ll go try it.

 

@ShimStack

Very fitting avatar...

 

I think you're supposed to have it in N and 4lo when you mess with that switch.

 

I can work with that.

What is “set the rear differential to the free condition”?

 

Have it unlocked.

 

Duh. Thank you.

 

I doubt this will make any difference. The service manual probably tells you to do it in 4LO because that's the only condition you can actuate the locker and thus inspect the switch.

No way should your diff be locked without a button press, current to the solenoid, and indicator light on the dash. Something is very weird.

 

You may be onto something with the over insertion of the sensor. When the switch indicator is out of the diff, it’s unlocked. When I install it, it locks.

 

Thank you all the advice so far! If you folks have any more ideas I’d love to hear them, I have most of tomorrow to mess with it.

I’ve plugged the old broken sensor with RTV so I can seal the hole in the diff. 4wd HI and LO both work, so I’m going camping either way!

 

Picture of new and old indicators side by side?

 

Unfortunately, I was a little rough with old one when I was trying to figure out how the mechanism worked... and now it’s packed full of RTV. They *seemed* the same size, but I honestly didn’t put them side-by-side.

 

You removed the carrier completely to install the sensor right?

 

The reason I ask is because if you didn’t remove the carrier and just jammed this sucker in there somehow there is no way the tip is aligned properly on the inside of the sensor ring. Chances are it’s pushing on that ring and not only scraping but also forcing the diff into the locked position. Also not sure how you got the old sensor out without either breaking off the tip or pulling it past the ring which likely bent it and is going to cause issues with an intermittent locker indicator light even when the diff is unlocked.

 

Ding, ding. Winner. Good pic. It actually hooks other side of the position plate. I checked the FSM too and the removal and install is done with the carrier out. He's jamming it straight in there and pushing the plunger in and locking the diff.

 

It would actually be the plunger pushing on the sensor ring enough to force the diff into the locked position. The plunger is a “pull” not a “push” so if he is jamming it in there is no movement on that plunger. The plunger piece is part of a sensor only not an actuator. If you remove the sensor all together the locker will actually function fine you just won’t have an indicator.