Xerox WorkCentre XK50cx Service Manual page 63

5-4 Defective Operation
PROBLEM
Open at on panel
does not openate
LF motor does not
operate
SCAN motor does
not operate
ADF motor does
not operate
CR motor does
not operate
Check paper
ITEMS TO BE CHECKED
• Powered up ?
• VCC(+5V) M+4.5V?
• Is the level of U15-127(_POR) high (more
than =4V)?
• Check Main to OPE harness and
CN11(main).
• Is the level of U15-54 (GP06) high (more
than +4V)?
• Check control signals of U15-123,
124(OPE_TXD, OPE_RXD).
• Check OPE key contacts.
• Check the harness contact.
• Check the control signals of U15-139-144
in Main PBA.
• Check the motor signals of U42-1, 19
and U43-1, 19 in Driver PBA.
• Check the harness contact.
• Check the harness contact.
• Check the control signals of U16-50~55
in Main PBA.
• Check the motor signals of U18-1, 19
and U19-1, 19 in Driver PBA.
• Check the motor sighals of U23-1, 19
and U28-1, 19 in Driver PBA
• Check the harness contact.
• Check the control signals of U15-32-34 in
Main PBA.
• Check the motor signals of U6-1, 19 in
Driver PBA.
• Check the paper jamming.
• Check the ASF.
• Check the sensor output in Main PBA.
• Otherwise
HOW TO SOLVE
• Check power.(SMPS)
a) Check if the cord is properly connected.
b) Check each power channel.
(+5V, +11.75V, +30V)
• Check power harness.
• Check the circuit around U13.
• Replace defective parts.
• Check the state of data bus of U15.: Replace the
main PBA.
• If signals of OPE_TXD are defective, replace the
main PBA. If signals of OPE_RXD is defective,
replace OPE PBA. (Refer to circuit explanation.)
• Replace OPE.
• Check CN1 contact in Main PBA, CN10 contact
in Driver PBA, and CN17 in Driver PBA whether
each connection is tight.
• If these CMOS signals are defective when the
other functions normal, replace the Main PBA.
• If these 30V signals are defective when the other
functions normal, replace the Driver PBA.
• Check CN1 contact in Main PBA, CN10 contact
in Driver PBA, and CN3 in Driver PBA whether
each connection in tight.
• Check CN1 contact in MAIN PBA, CN 10 contact
in Driver PBA, and CN4 in Driver PBA whether
each connection in tight.
• If these CMOS signals are defective when the
other functions normal, replace the Main PBA.
• If these 30V signals are defective when the other
functions normal, replace the Driver PBA.
• Check CN2,CN3 contact in Main PBA,CN13,
CN16 Driver PBA, and CN2 in Driver PBA
whether each connection is tight.
• If these CMOS signals are defective when the
other functions normal, replace the Main PBA.
• If these 30V signals are defective when the other
functions normal, replace the Driver PBA.
• Check the real jammming in paper path, and
remove it.
• Check the ASF according the "Paper Feed".
• Check 5V of U16-68 when the sensor lever is
interrupted, and 0V of U16-68 when the sensor
lever is lifted. If the sensor is defected, replace it.
• Replace the Main PBA.
Troubleshooting
5-7