Logitech K850 Disassembly

Written By: Marcus Jones

Comments: 11

Difficulty

Moderate

Steps

Time Required

15 - 30 minutes

Introduction

Tools

Step 1

Pry open the battery cover on the back of the device using either your hand or a spudger.
Use a spudger to remove the first battery.
Slide the 2nd battery out of the slot.

Step 2

Unscrew the highlighted red screws using a Phillips 000 screwdriver.
Some screws are hidden under the rubber feet so you will have to pry off the rubber feet.
There are 2 screws under the keyboard's kickstand.

PH000 was way to small/wobbly for my KBD (maybe the size changed over the years).

PH0 was perfect match

ZZZ ZZX -

Step 3

Insert a spudger into the seam between the black side (front) and the white side (back).
Pry the two halves apart, making your way around the keyboard.
Be careful while prying, or else you may break the two plastic clips that hold the sides together.

I think it would help to have a photo with arrows showing where the clips are and which way to pry to release them.

David Limbert -

I was able to use slotted 3/32 tip (from Husky 74501 set) - the other side of PH0

ZZZ ZZX -

Step 4

Flip the black side (front) over so the keys face downwards.
Remove the red highlighted screws, then remove the palm rest.

Step 5

Unscrew the circuit boards using a Phillips 000 screwdriver.

Great guide. Are replacement circuit boards available?

Dan -

Step 6

Use a pair of tweezers to bring the metal rods under and over the plastic hooks.
Approach with caution, you can break the metal rod and/ or the plastic hooks if you are too aggressive.

Step 7

Unplug the ribbon cable connecting the two boards and remove the power switch daughter board.

Unplug the ribbon cable connecting the two boards and remove the power switch daughter board.
Unplug the ribbon cable connecting the membrane to the main circuit board.

Nice guide, thanks.

Any idea whether or not one can purchase a replacement power switch daughter board?

Dan -

Would anyone have an idea why would 4 keys on the same printed circuit line [F1 1 2 T] fail to recover after cleaning/drying spilled wine? Membrane was supposed to prevent liquid from going further but it didn't. No visible damages to the circuit. The fn keys (on the same line as these 4) appear to be functional, except that pressing them alone (without an F-key) lights up current connection indicator [1 - 2 - 3]. Don' know if that's normal behavior on a virgin KBD.

Z Z -

The circuit under the membrane is multi-layered, maybe the wine got in between the layers.

Marcus Jones -

How do you suggest what to use to thoroughly clean the membrane parts of the keyboard?

Can they be washed in warm soapy (like dawn) water and dried with warm hair dryer?

Michael Rosen -

Warm soapy water works well to clean the membranes. Do pay attention to the temperature of the membrane, as it can get very hot to the touch easily.

Marcus Jones -

Conclusion

The Logitech K850 keyboard is quite complex, though it is somewhat easy to fix. However, with a ton of fragile components that need to be pried on, repairs can be difficult.

Author

Marcus Jones

Member since: 23/11/18

1241 Reputation

2 comments

How do I fix the incredibly tiny plastic piece where the foot/stand fits into? Are the side wholes enough to get two new feet without having to worry about that plastic part or does it need ot hook into that?

Danny Romero -

It is difficult for key plucker to remove keys from.mk850 . Is there a easy way to remove keys from it?

Suman Kalyan - 30/06/24