Picade display flash blue then blank

Support
1

Hello so I have finished building my picade when I use an external monitor every thing works great the included monitor flashes blue then blank when I power it up. I have tried it with it’s own power supply the same thing happens I have also reseated the ribbon cable same thing happens.

Thanks

2

Have you tried adding the following into /boot/config.txt?

hdmi_force_hotplug=1