Sovol 40W/5W laser on 3018 cnc

Hi, trying to get my 5W laser to work with 3018 cnc but having problems…
Running GRBL 1.1 on LaserGRBL to check GRBL settings.

I have watched all the Sovol videos adding the laser to your 3d printers but this does not help me.

When I connect the power cable (2 pin) into my 12v laser printer output on my cnc controller board and the other end of the power cable to the laser head Power (also 2 pin) I get nothing. Turning laser on/off via LaserGRBL does nothing (using built in buttons or console).

Connecting the same power cable to a different 12v power output from GRBL controller board to the laser and the laser comes on but will not turn off…

I am hoping to get the laser working from the controller board rather than external power supply even if I cannot get it at full power but I cannot find the power draw (Amps) that the laser requires. Any help would be appreciated please.