I just acquired a '96 SR to replace my '95. (I've been away far too long. Hopefully I can get back on the trail soon)

When I shift into 4 hi locked the center diff won't lock up. The orange light on the dash never stops blinking. I've tried letting off the gas, giving it gas, while moving, while in neutral, etc. I've also tried shifting into 4 lo. That doesn't help either.

It has 110k miles and it's possible that it's never been put in 4 hi locked before.

Any suggestions of what I should look for?

Thanks,
Kirk

'96 SR, 35's, body lift, arb front bumper, Custom rear rock bumper, rock sliders.
'89 Raider V6 w/ SR rear axle & locker
Kirk's Montero page but not updated in forever
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