Nikon rangefinder power and mode buttons frozen/stuck

[rossfrb]

So couple of months ago I used my Nikon laser range finder - then put it away in its bag and then back into its box (yes I am that sort of person) and then into a cupboard. Last week I take it out, un box it and go to use it but both power and mode buttons are frozen. No actuation, no give, no click whatsoever. So I buy a new battery and replace (in the correct orientation) still no luck. Swapped battery orientation just to see what that would do, still no dice. Left the battery out overnight and put back in correct orientation, still frozen.
I'm scratching my head. The unit wasn't dropped or banged about prior to storage after the last successful time I used it.
There are no screws or any way to disassemble that I can see, nor a reset button or hole.
Model is LRF1200
What can cause buttons to freeze or stick?
Short of sitting it under a crystal pyramid during a blood moon or loosening with a sledgehammer, any suggestions?
Regards
rb

[Flyonline]

Can you take the cover off and squirt some electrical contact cleaner in the physical switches (not just the rubber/plastic bits)? Or better yet give it a blast with clean air first to see if there's a bit of dust/grit in there causing it to malfunction.

[rossfrb]

The unit seems pretty tightly sealed up. No way I can see to disassemble. Also it's supposedly waterproof. Guessing any squirting of anything isn't going to penetrate too far.
The thing that has me stumped is that both buttons are frozen. If it was some sort of physical obstruction why both buttons?
If I'd dropped it on the floor or in the dirt or in a bucket of water then I could understand why it might be all locked up - but it was working fine prior.

[jezzab]

Did the buttons give a tactile feedback before (ie did it click, pop or anything you can feel that you pressed the button)? Personally IF it wasn't IP67/8,sealed like it looks, I would use some IPA vs contact cleaner, doesn't rip up the plastics. That's assuming you had tactile feedback.bwfore, if you didn't then yeah, it's a power/software issue

[rossfrb]

Yes there was definitely tactile feedback, the buttons would depress/click a little.
Sorry, what do you mean by IPA vs contact cleaner?
The only IPA I know is hopped and fizzy and best enjoyed cold.

[No1_49er]

IPA = Iso-Propyl-Alcohol (or, India Pale Ale )

You haven't said how old the device is.
Have you considered taking it back to the vendor and making a warranty claim - not fit for purpose, or, of merchantable quality?

[straightshooter]

The unit seems pretty tightly sealed up. No way I can see to disassemble. Also it's supposedly waterproof. Guessing any squirting of anything isn't going to penetrate too far.
The thing that has me stumped is that both buttons are frozen. If it was some sort of physical obstruction why both buttons?
If I'd dropped it on the floor or in the dirt or in a bucket of water then I could understand why it might be all locked up - but it was working fine prior.

Step 1
If the rangefinder is less than say 5 years old you might try contacting Nikon headquarters and complaining about the durability of the unit.
Failing that then you are on your own
Step 2
Leave the unit out in the sun for a couple of hours so the unit fully warms up internally. If it then operates correctly that means the congealed internal switch lubricant was preventing it's tiny ratchet mechanism from functioning correctly. If you are in luck that might be all it needs.
Step 3
If you are adventurous.
Very carefully prise off the decorative rubber cover with it's press button covers which should be integral. If you tear it then there goes any waterproofing. Use something like a paddle pop stick sharpened like a chisel. The rubber cover might have moulded in teats that fit in holes in the plastic so be careful. With that lifted off it should be obvious how to further dismantle the unit but if the switches are easily accessible then just try spraying inside the switches. I would be inclined to spray with 3 in 1 silicon spray.
Test the switches for operation. If you feel and or hear a positive click but the unit still does not work then the likely culprit will be either corroded contacts or contacts that have lost spring tension.
If it works then use an adhesive to reglue the decorative cover.