D850 won't turn off ?

[IanOliver]

My D850 won't turn off. It hasn't been dropped or banged around at all. Just noticed this yesterday but it could have been happening for a while as I never really check to see if it's actually off when turned off. Has anyone else experienced this?

[bob_flood1]

I don't have D850, but a couple of things apply no matter what body is involved.

 

First, it WILL turn off if you remove the battery. Do so, and keep the battery out for a minute or so to allow any capacitors inside to drain stored charge. Then put the battery back in. Does the camera come on even though you haven't used the on/off switch? If it does not, then turn the camera on. Does it turn on? If so, can you now turn it off? If you can, keep checking the on/off for a few days to see if the problem arises again.

 

If you get no good results from all that, then a 2 button reset would be appropriate. Consult your manual to get the correct procedure and do the reset. Then test to see if the problem persists.

 

If these don't work, I suspect a trip to Nikon's service center will be necessary.

[Matthew Currie]

Is the memory access light on? I have had similar problems a couple of times with a D7100 - too seldom to figure out the reason and it's recovered by removing the battery. But it seems to involve a faulty attempt to write to the card.

[ShunCheung]

I have had this issue once with a D500 when it was quite new. It happened in the middle of a safari in Bostwana in Southern Africa, in June/July 2016. (Recall that the D500 was announced in January 2016 and I bought mine in May.) I was concerned as obviously I didn't want to lose a body in the middle of an important trip, although I had two other bodies with me. I took the EN-EL15 battery out for a few seconds and then re-inserted the battery back in. Fast forward another 2.5+ years and this problem has not occurred again.

[mike_halliwell]

I have had this issue once with a D500

 

... yup, same with my D500. Thought it was me..although how, I don't know!

 

I suspect, as Matt said, it's a glitch with still thinking it's writing to card and CANNOT turn off. Don't remember the memory light though.

[ShunCheung]

In the case of the D500, back in 2016, some people, including Thom Hogan, figured out a sequence of buttons to press to reproduce the "cannot switch off" situation. I have never paid much attention to that process, but apparently one can reproduce that error on a regular basis as long as you follow that procedure:

 

A Reproducible D500 Lockup | DSLRBodies | Thom Hogan

 

I have no idea how I got my D500 to lock up while I was in Africa, but my D500 has been working normally after I removed and then reinserted the battery.

 

The D850 lockup maybe a different issue, though.

[david_r._edan]

99% it's got something to do with your memory card. Try using a different one.

[IanOliver]

Pulling the batteries for a bit and re-inserting seems to have done the trick. I should have thought about that. Hopefully it follows in Shun's path and doesn't reappear.

 

Thanks everyone!

 

BTW, though it seems, so far, to have not been the memory card, I'm curious how that could do it?

[bgelfand]

BTW, though it seems, so far, to have not been the memory card, I'm curious how that could do it?

 

Since I have neither the circuit diagrams nor the code for the firmware of Nikon cameras, this is supposition but ...

 

Everything on modern cameras is software drive, including turning the camera off (the off switch does not really "turn it off i.e. cut the power, it just puts it to sleep - a deep sleep.) If the camera is locked in a write loop, the interrupt generated by moving the power switch to the "off" position is masked - in fact all interrupts may be disabled - so the computer running you camera never receives the command to go to sleep. Of course, pulling the battery and allowing all the capacitors to discharge does "turn off" the camera. When you inset the battery, the CPU in the camera goes to power on boot up state - usually executes a hardwired instruction at a predetermined location in memory in the firmware that contains a JUMP command to the initialization routines in the firmware.

[wythe]

I also have been intermittently experiencing this with my D850. First happened in Fiji in high temperature and humidity and seemed to stop when I came home but is happening intermittently. When it was happening I had to pull the battery whenever I wasn't using the camera. Will look to see if it seems to be processing a photo or something else when it does it. The camera works fine otherwise.

[ShunCheung]

As I mentioned earlier, this happened to my D500 exactly once, when it was quite new. If this problem has happened multiple times, I would get the camera fixed. IMO it is I longer dependable.

[bgelfand]

Try replacing the memory card. If this happens when the camera is writing to the card (whether the write light is on of not), it could be the card. If there are two cars in the camera, try removing the second card. Of course if the camera is under warranty, get it to Nikon before the warranty expires.

[Ed_Ingold]

It has occurred at least once on several Sony cameras I have owned, and before that, a series of Nikon D this or that.

 

Digital cameras are computers with a lens, and as such can lose their minds on occasions. The power switch is just another input, not a power interrupter. That allows a vital operation, like saving an image, to proceed to completion, without corrupting the image or card. Sometimes an operation never completes, and there you are.

 

Turing the switch off, then removing the battery for a few seconds does the job of rebooting, and restoring normal operation. If a card is corrupted in the process, it may not work afterwards. Change cards, and recover the images if possible (or set it aside for a more "forensic" operation later).