bradcope

I have a 1995 Waveraider Deluxe (RA700AT). The PWC runs fine, but the multi function display does not show any information. There's power on the red wire to the display, but no power on the green wire. The shop manual shows power should be on both. The green wire originates at the electrical unit (EU). The fuse is good in the EU. I have the shop manual, It shows where the cables are routed and it walks you through how to test each sensor, but it doesn't give a complete map of where each wire connects and it's function. Like I know the green wire goes between the EU and the MFD, but what logic has to happen before the power is applied to that wire? Is there a more detailed electrical schematic for this PWC so I could trace the circuit? Should I remove and inspect the EU? What steps should I take to troubleshoot this condition? The PWC is new to me and I think it's something simple and I want to be methodical in finding out what's going on here so any experience or information would be helpful in helping me piece this together.