Z6200 with Blank Screen after replacing Trailing Cable/Ink Tube Assembly

[KeppsQ]

Confirmed that the printer had the reported error of 86:01 (Carriage Servo Shutdown) that wouldn't clear. During troubleshooting I noticed that there were tiny metal threads along the carriage path and then found that the Trailing Cable rubber and braided metal shield had worn off in multiple places. Came back with the Trailing Cable/Ink Supply Tube Assembly and installed it. I don't know if an HP original part would have the Ink Tube PCAs on each, but the refurbished part I got from a trusted vendor didn't have them so I had to swap them. When I powered the unit up, the first thing that happened was that the front panel was blank (lit up white background, no black rectangle) and no initialization. I shut it down and restarted. Next time, same blank screen then I started hearing a continuous trilling type beep noise, so I quickly turned it off again at the main power. I started troubleshooting the rear LED's.  At power up and observing the Power Switch LEDs, I saw the amber light, it went off, then the blue light at the same time as the trilling noise, then it would cycle back to the amber light and continuously repeat this cycle. Finally, this stopped, both blue and green LEDs stayed on and the Formatter fan turned on, but still no display or other initialization. The Formatter LEDs I and II are both on. The Service Manual troubleshooting table for both those sets of LEDs doesn't list an option for Formatter LEDs I and II on plus Power Switch LEDs Blue and Green, so that is no help. I unplugged the HD and it powered up with 8 beeps, so I think I've ruled that out. I powered up with the trailing cables disconnected with no change. Leaning toward the Formatter, although it doesn't match the troubleshooting table and  seems odd that this happened right after replacing other parts. Also wondering if maybe one of the Ink Tube PCA's is pulling down the Power Supply. Any help or suggestions would be greatly appreciated! 

Thanks.