I’m newish to the K40+ and just trying to get this figured out..
i hae an Omtech K40+ build in jun 2025, the laser display is now showing anything. .Key is on, power is on, the mainboard can receive and move the engraving head.
there is a redlight on top of the powersupply and the test button on the power supply itself doesn’t work to fire the laser..
i’m at a loss where to even start to diagnose this problem
The fire button on the laser power supply(LPS) should fire the laser if the other safety signals are pulled to the correct level. Have you looked at the K40 Intro link in the upper right corner of this page and look for trouble shooting?
If you LPS is setup properly and the fire button on the LPS still doesn’t work then you’d be looking at a tube and/or LPS replacement. K40s are very often over driven and prematurely kill the tube because the digital displays often overdrive the tube when set to anything above 40%.
You would do well posting a picture of your front panel and then a picture of your controller board.
And a K40+ is a CO2 laser, not a fiber laser so now we are really confused as to what you have.