Xerox DocuColor 12/DCCS50, Service Manual

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2-165 DocuColor 12/DCCS50
10-375 Pressure Roll Control Thermistor Overheat
Status Indicator RAPs
Reissue
10-375 Pressure Roll Control Thermistor Overheat Failure
RAP
The Pressure Roll Control Thermistor detected a temperature in excess of 230 ° C (446 ° F) on
the Pressure Roll.
NOTE: This status code is stored in NVM location 777-160 and cannot be reset by Power Off/
Power On. To reset this code, enter Diagnostics and change the value in NVM location 777-
160 Fuser Over heating Failure from 3 to 0.
Initial Actions
Refer to BSD 10.2 and 10.12 for the following procedure.
• Open the Drawer and extend it to the service position. Perform the following:
–
Remove the Oil Cartridge ( PL 8.1 ).
– Remove the Front Cover ( PL 8.1 ).
– Remove the Top Cover ( PL 8.2 ).
• Check the Pressure Roll Control Thermistor for cleanliness, damage and excessive wear
at the point where the Thermistor contacts the Pressure Roll. If the surface of the Ther-
mistor is worn, replace the Pressure Roll Control Thermistor (
PL 8.6 ). Inspect the surface
of the Pressure Roll for excessive wear due to the Thermistor. Replace the Pressure Roll
if necessary (
PL 8.3 ).
Procedure
NOTE: Prior to replacing a component, disconnect the connectors to the component (Pressure
Roll Control Thermistor and IOT Drive PWB). Check the connectors for broken, bent and dirty
pins. disconnect and reconnect the connectors several times to remove contaminants due to
oxidation.
Ensure NVM location 777-160 is reset to 0. Switch off the power. Cheat the Front Door Inter-
lock Switch. Disconnect
P/J173 on the Pressure Roll Control Thermistor. The resistance of the
Thermistor should be in the range of 0.78K Ohms when hot, to 150K Ohms when cool (room
temperature).
The resistance is in specification.
Y N
Replace the Pressure Roll Control Thermistor ( PL 8.6 ).
NOTE: To remove the harness guard ( PL 8.6 ) around the thermistor wires, press the tab
on the guard that is located below the front cam ( PL 8.6 ).
Reconnect the connector. Close the Drawer. Switch on the power. The 10-375 fault is
declared immediately after self-test completes.
Y
N
Switch off the power. Check the voltage at P/J105
-3 on the SSR and GND. Switch on the
power. There is 0 VDC present when self-test completes.
Y N
The voltage at
P/J105
-3 increases to approximately +4.3 VDC within 12 min-
utes.
Y
N
Replace the IOT Drive PWB ( PL 9.2
).
The Heater Rod remains illuminated while P/J105 -3 still reads approximately
+4.3 VDC.
Y
N
This indicates that the problem is intermittent. Replace the Pressure Roll Con-
trol Thermistor (
PL 8.6
).
Replace the SSR ( PL 9.3 ).
Go to Flag 7 ( Flag 17 w/ Tag P31) on BSD 10.2 and check the harness for a short circuit
to ground. If OK, replace the IOT Drive PWB ( PL 9.2 ).
Go to Flag 5 on BSD 10.2 and check for a short circuit to ground between P/J173 -1 and P/
J413A -9. If OK, replace the Pressure Roll Control Thermistor ( PL 8.6 ). If the problem contin-
ues, replace the IOT Drive PWB ( PL 9.2 ).
A
A
B
B
C
C