Dfe/Ess Communication Failure 9 - Xerox DocuColor 2240 Service Manual

16-379 DFE/ESS Communication Failure 9

ACK not received after 2 resends because an overrun error was declared by the IOT hard-
ware.
Procedure
Switch the power off, then on. If the problem continues, check the connections at the MCU
PWB and the I/F PWB. Check that the DDI cables from the Network Controller (NC) to the IOT
are secured and are free from damage. Reinstall system software.
If this does not resolve the problem, perform the following checks in the sequence presented,
until the problem is resolved:
• Ensure that a live network cable is connected to the NC. Verify that the AC power connec-
tor is connected to the NC and that AC line voltage is present. If the voltage is not present,
go to the OF 1-4 RAP.
• Verify that the NC is functioning correctly. Refer to the NC service documentation.
• Switch the DDI cables from the NC to the IOT (switch both ends). If the problem changes,
replace the cables.
• Replace the VSEL PWB (PL 13.1).
• Replace the ESS PWB (PL 13.1).
• Replace the MCU PWB (PL 13.1).
If the problem persists, replace the Network Controller.
Status Indicator RAPs
16-379, 16-380
16-380 DFE/ESS Communication Failure 10
NAK-generated sequence number error.
Procedure
Switch the power off, then on. If the problem continues, check the connections at the MCU
PWB and the I/F PWB. Check that the DDI cables from the Network Controller (NC) to the IOT
are secured and are free from damage. Reinstall system software.
If this does not resolve the problem, perform the following checks in the sequence presented,
until the problem is resolved:
• Ensure that a live network cable is connected to the NC. Verify that the AC power connec-
tor is connected to the NC and that AC line voltage is present. If the voltage is not present,
go to the OF 1-4 RAP.
• Verify that the NC is functioning correctly. Refer to the NC service documentation.
• Switch the DDI cables from the NC to the IOT (switch both ends). If the problem changes,
replace the cables.
• Replace the VSEL PWB (PL 13.1).
• Replace the ESS PWB (PL 13.1).
• Replace the MCU PWB (PL 13.1).
If the problem persists, replace the Network Controller.
02/03
2-332
Initial issue
DC 3535/2240/1632