MX-M363N E7-80 error

[audyplongo]

hi everyone i have a sharp machine with this E7-80 error i looked it up and got this :

• Code: E7-80
• Description:Communication trouble (ICU detection) between ICU and scanner
  Communication establishment error/ Fleming/Parity/Protocol error
• Causes:Defective connection of slave unit PWB connector Defective harness between slave unit PWB and ICU PWB Slave unit PWB mother board connector pin breakage
• Remedy:Check connector and harness of slave unit PWB and ICU PWB. Check grounding of machine.

but my issue is that i looked in the parts manual and cant find what matches this part called the "slave unit" so if someone could please point me in the right direction or has any other way to clear this error i have cleared it a couple times and it went away for about a week but it keep coming back also not sure if this is part of the issue but sometime the UI does not work when pressing buttons on the panel it does not do anything any suggestions would be appreciated.

thanks

[Prints Charming]

E7-80 is a communication breakdown between the MFP and SCU board, usually caused by a problem with the DC Power Supply or a harness/connector.
The Slave Unit you mention is the Motherboard, which is the tall, vertically mounted board next to the MFP board.
The Motherboard powers and interfaces between the MFP, SCU and PCU. The Motherboard distributes power to these boards, as well as the LSU on some devices.
Check all voltages from the DC Power Supply to the Motherboard. You'll see a large connector in and a large connector up top going to the SCU board.
A drop in voltage will cause a problem like you are experiencing.
Motherboard is shown in the Control Box section of the Parts Guide.
Your problem is almost surely going to be the Motherboard or DC Power Supply.