Some years ago I have purchased a second hand cargo fire panel, but it was never connected until now.
I started working on a plan to connect it and once finished, the plan was executed. The one lowlight is that the Discharge button was glued into the panel, so I had no chance to use it. Therefore the function of this switch was moved to the aft. overhead, as I had there one free unused button.
It turned out that I had to fully adopt the panel for my need. The 2 LEDs in the Pushbuttons were connected on their cathode and will light up when +5V are connected to the anode. But my Setup with the Opencockpits cards have the anode in common and the cathode the switched one, so the 2 buttons have to be reassembled to meet the requirement. One button worked fine with the second one the LEDs got destroyed. So I have to reinstall 2 new LEDs and connect them.
Also the 2 green lights were 12V light bulbs, which you cant see with 5V. Therefore those were changed to green LEDs.