Cant engage diff lock. HELP!

[Wallknight]

2006 CX. Diff lock won't engage. More accurately, diff doesn't engage AT ALL in 'unlock', and engages in the 'unlock' mode when lever is in the 'lock' position. The cable DOES move the little rectangle thing on the diff. Though it does seem like it should move it a little bit more.
Meanwhile, where are the markers on the trans dipstick? It was getting dark, and I was standing in a cold puddle, but it looks like the only fluid is way down in the bottom of the housing. Should there be more? Are there marks somewhere on the yellow dipstick I missed by flashlight? if trans fluid is low, could it be causing my diff lock issue?

Presently stuck spinning 1 tire in 1" of mud...

[Wallknight]

rear on jacks. forward gear. engine on. no wheelspin on unlock. only right tire spins on lock. left is completely free to spin in both directions with my foot.

Broken axel? Or diff?

[200mph]

Sorry I can't provide any guidance.

Might be worth purchasing a workshop manual. I've found them invaluable and very satisfied with the pictures and technical detail.

Good luck and keep us posted with what you find.

[Wallknight]

Diff was shot; internal gears destroyed. Can not longer get the gear-only kit, had to get the $300 total diff. Btw- no one has pics. for $300 you get the complete diff. outer ring gear, 4 gears inside, all assembled, ready to be dropped into the gear box.
Not too hard of a fix. one tip: You gotta split the box into all 3 parts. then there are holes on the outside of the diff box, through which you can put a pole to pound the diff out. It's pressed into the box with a bearing. Otherwise, pretty straightforward.