TL;DR - How do I re-wire this board to swap the button functions?

The whole story:

This is a bit of an odd question, and if there's a better forum (or even a more appropriate website) please let me know.

So, I work in an office that has a projector screen that retracts into the ceiling. On the wall there are switches that control the screen. This is very nitpicky of me, but whoever installed the switches managed to make it so that the up-arrow-button makes the screen go down, and the down-arrow-button makes the screen go up. To fix the problem, they just rotated the switch board 180-degrees so the arrows are pointing in the correct directions. BUT... in between the arrows is a button labeled "STOP". Because of the rotation of the switches, the stop button is now upside down.

switch locationswitch

I'd like to fix this problem somehow and I'm hoping someone can tell me how I can swap the up and down button functions, which will then allow me to rotate the switches 180-degrees back to their intended position so that the stop button will be right-side-up.

I'm thinking I just need to re-solder the wires in a different configuration? If so, how do I need to rearrange the wires?

I'm a complete noob to this sort of stuff, but I'm very interested in things like this and am willing to get a soldering iron and whatever other tools I may need to do the job.

Thanks in advance for any help you can provide!

Video of me rotating the board: https://photos.app.goo.gl/6Fuhjh5B6NTe2eDK9

exposed board front exposed board side exposed board rear

  • Resoldering wires may or may not work but the board needs better reverse engineering to see if it is possible. Might be easier to swap the functionality in the other end of the wire, but we don't know what kind of controller there is. Can you simply rotate the stop button keycap which would fix the issue too?
    – Justme
    Commented Mar 5, 2021 at 21:29
  • 3
    Someone got the word "STOP" into the button cap. It's square so you should be able to prise the cap off and invert it.
    – Transistor
    Commented Mar 5, 2021 at 21:48
  • The cup of button might be removed with small slotted screwdriver. It usually slip-on.
    – user263983
    Commented Mar 5, 2021 at 22:19
  • if forced to guess swapping red and black looks best.
    – Jasen
    Commented Mar 5, 2021 at 22:51

2 Answers 2


That is a Somfy IGC switch. The wires are Red=+12V, White=UP, Black=Down. So you need to swap black and white to reverse the function. You would likely find a terminal block on the controller where you could rewire this without soldering.

This is the typical wiring scheme for Somfy IGC switches. There is some possibility that the installer used different color scheme. This should be verified at the control box. Wiring scheme for Somfy Modular wires.

Here is a typical wiring diagram for Somfy motor controls. This diagram shows the use of the modular wiring, but the terminal block info is there on the right.

Typical wiring diagram for Somfy motor controls.

  • Just wanted to emphasize this answer. It's rare for this type of component to be soldered in the field(although the orange and blue wire stubs make me think that may have actually been done in your case), so checking the wiring of the controller is a logical next step.
    – K H
    Commented Mar 6, 2021 at 5:49
  • The orange and blue wires are cut off at the board. They are also cut off just inside the wall where this cable is again stripped and the red, white, and black wires are attached via twist caps to their corresponding wires that run up to the projector screen. Since I'm a total noob with this stuff, what does "controller" refer to? Is that a component that would be found up in the projector screen assembly?
    – Addison Scott
    Commented Mar 6, 2021 at 23:02
  • Somewhere between the switch and the motor on the screen, there is a control box. You should be able to switch the wires on a screw terminal block there. Commented Mar 6, 2021 at 23:30
  • @ScienceGeyser Great, thank you for adding the diagram! First I'll see if the button is easily rotated, but I don't want to break anything by prying too hard. If that doesn't work, I'll try to find the control box so I can swap the wires.
    – Addison Scott
    Commented Mar 7, 2021 at 1:23

Photo of the bottom side of the board with the cable out of the way - ?

It might be that the switch assembly has perfectly symmetrical pins, and the assembler installed the switches rotated 180 degrees. If so, then someone with rework skills can unsolder the switches and reinstall them correctly.

OR -

If the lettering is under the switch cap, you might be able to pull/pry it loose. You might need something like an X-acto knife blade to get down in there. I've found a #16 blade to be a bit more robust than the standard #11.

  • 1
    +1 on just flipping the physical button with no involvement for the electronics. This will be vastly easier and more likely to actually work
    – BeB00
    Commented Mar 5, 2021 at 23:21
  • The switch assembly is not symmetric, so it would not be possible to unsolder the switch assembly, rotate it 180-degrees, and resolder. there are two pins for each button and they are not symmetric with the centerline of the switch assembly.
    – Addison Scott
    Commented Mar 6, 2021 at 22:55
  • The switch assembly is made of an upper housing (which has the holes in it for the button caps) and a bottom housing (out of which come the pins which are soldered to the board. The joint between these two parts of the button housing is covered by stickers on both sides, so I was hesitant to cut through the stickers and pry the upper portion away and thereby hopefully gain access to the stop button cap and rotate it. That is a good idea though about trying to use a thin blade to try and pry the cap out of the upper housing.
    – Addison Scott
    Commented Mar 6, 2021 at 22:58

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