Laser not firing on projects

Purchased K40 laser, changed power supply, upgraded to Cohesion3d board using the Smoothieware.

  • Stepper motors work and I can navigate points on project (using Lightburn) however laser will not fire.
  • Laser will fire if “test” button is pressed on power supply.
  • checked all connectors (4 blue wires from board to power supply) and all are connected. I did not reconfigure the wires from the prior power supply and it was a direct plug in with the same plug attachment. 24v/G/5V/L

I am not sure why the laser will not fire on the project.
Please Help!

Did you connect the PWM line of the cohesion board to the TL port of the power supply? (Not sure its needed on the cohesion as it seems to be included in the 4 PIN header for power supply, on MKS SBase you need to make that connection as well.)
But one thing which happened to me was not to activate the Laser main switch on the panel

Thank you for responding back!
The 2 pin PWM port on my Cohesion Board is currently not in use . Does this process include placing a 2 pin connector on the PWM line port and then connect this over to the power supply TL connector / G ?

Actually I don’t know the cohesion board. I would guess that this connection is already done with the 4 Pin Power connector as the most right one on the power supply ist the L line already. I would suggest to check this with the support forum of Cohesion3D.
Otherwise I could only imagine that the Laser fire button is not activated.

You will get proper answers if you post directly to the very nice folks at:

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