Groove Coaster Fast IO error 501 and 502

[ChuckCasey]

I have 4 Groove Coasters. Three Link Fever 3s and one 4.

Two of the Link Fever 3 machines are experiencing FAST IO errors. Error 502 (Fast IO Universal PCB recognition - check the connection from Fast IO Hub to Fast IO Universal PCB)
I've tried tested and proven network cables from Hub to Universal with no resolution. I've tried every output on the HUB too. I've also changed the network cable from TypeX main PC to the HUB.
I've tried each in other machines. The issue follows the PCBs.
Checked both the 5vdc and 12vdc to the HUB and Universal PCB (both good)

Do I need a special network cable?

Any tips or tricks on solving this Fast IO error?

Thanks !!

 

[nem]

I've tried each in other machines. The issue follows the PCBs.

Which PCBs have you swapped? The motherboards?

 

[ChuckCasey]

I swapped Fast IO HUB and Fast IO Universal PCB (as a set) and separately the Main "SHIELD" Type X-0 PC.

I have two working Groove Coasters that have NO errors. I could swap with a 100% working Fast IO board set but get worried if there's something in the machine (wiring harness, ground, etc) causing the problem I can't afford to damage another Fast IO board.

I'll be reflowing solder on the network and other connector joints on both boards within the hour and testing later tonight.

Since I have the ERROR 502 on two Groove Coasters I was hoping that someone else has had this "common" issue.

I'm also willing to buy a Fast IO board set or individual boards if someone has them for sale. The part numbers from Taito are K91X1251M and K91X1252M.
Or if anyone knows of a Taito US distributor or reseller I'd appreciate the advice.