Chosen Solution

Date:Aug 19, 2018 I have a dbpower T20 projector and I want to replace the LED cob light with a different one that has an onboard driver so my question is how can I bypass the ballast and trick the motherboard into receiving the lamp signal.

The easiest way to do what you hope is to complete replace the light emitter assembly with one of your own. I have a high degree of confidence this will be more trouble than it’s worth. Not saying that it’s impossible, but it will take time, skill and lots of trial and error. I recommend you sell what you have while it still works and buy a new one that serves your purpose as built.