Xerox WorkCentre 5790 Series Service Manual page 83

01H Short Circuit and Overload RAP
Procedural Notes
Ensure that the electricity to the machine is switched off while performing tasks that do
not need electricity. Refer to GP 14. Disconnect the power cord. Electricity can cause
death or injury. Moving parts can cause injury.
• The LEDs, Figure 1, CR12, CR13, CR14, CR15 and CR36 on the IOT PWB are used to
indicate that a supply voltage is available. Refer to
• Short circuit or overload of +3.3VSB (standby) will result in all outputs off.
• Short circuit or overload of +3.3V or +5V will result in all outputs off, except +3.3VSB.
• Short circuit or overload of +12V or +24V will result in only those outputs being off.
• In all instances, when the short circuit or overload is removed all the outputs will recover
to normal operating voltages after 10 seconds.
• If +3.3VSB is over voltage, all outputs will be off. To restore to normal, switch off the
machine, GP 14. Wait two minutes. Switch on the machine.
• If +3.3V, +5V or +12V are over voltage, all outputs will be off, except +3.3VSB. To restore
to normal, switch off the machine, GP
• If the +24V is over voltage, only the 24V the output will be off. To restore to normal, switch
off the machine, GP 14. Wait two minutes. Switch on the machine.
Do not repair or install a new fuse F1 on the IOT PWB. Repairing or installing a new fuse
can cause overheating and a risk of fire.
Do not repair or install a new fuse F1 on the power distribution PWB. Repairing or
installing a new fuse can cause overheating and a risk of fire.
Do not repair or install a new fuse F1 on the main drive PWB. Repairing or installing a
new fuse can cause overheating and a risk of fire.
Do not install a fuse of a different type or rating. Installing the wrong type or rating of
fuse can cause overheating and a risk of fire.
Procedure
Switch off the machine, GP 14. Remove the rear cover,
cord. CR36 is on, Figure 1.
Y N
Go to 01J Power On and LVPS Control Signals RAP.
NOTE: To disconnect the connectors PJ16, PJ17, PJ18, PJ19 and PJ25 on the LVPS, open
tray 1 and tray 2. Remove the screw that secures the power and control assembly,
Slide the power and control assembly to the left.
NOTE: Refer to Figure 3 for the low voltage distribution. This is an overview of all the low volt-
age harnesses within the machine.
NOTE: Refer to GP 7 at every harness check and if necessary perform,
To check the output voltages of the LVPS, disconnect the following.
• Figure 2. PJ16, PJ17, PJ18, PJ19 and PJ25.
Xerox® WorkCentre® 5790 Family
WARNING
OF7 IOT PWB Diagnostics RAP.
14. Wait two minutes. Switch on the machine.
WARNING
WARNING
WARNING
WARNING
PL 8.10 Item 1. Reconnect the power
REP 1.2.
• Figure 1. All the PJ connectors on the IOT PWB, except PJ26
PJ5 Flag 15.
Press the on / off switch, PL 1.10 Item
Y N
Check for a short circuit on the AC line. Go to
Press the on/off switch, PL 1.10 Item
on.
Y N
Go to Flag 15. Measure the voltage at PJ5, pin 19. Press the on / off switch,
8. The voltage changes from +3.5V to 0V.
Y N
Check the wiring to the on / off switch,
switch, PL 1.10 Item
Disconnect PJ26. Measure the voltage at the harness of PJ26, pin 7,
available at pin 7.
Y N
Install a new LVPS and base module,
Reconnect PJ26. Measure the voltage at the harness of PJ26, pin 7,
on / off switch. The voltage changes from +1.16V to 0V and stays at 0V.
Y N
Install new components in the order that follows:
1. Install a new LVPS and base module,
2. Perform OF7
PL 1.10 Item
Disconnect the power cord. Use a service multi-meter set to DC amps. Ensure the meter
leads are connected to the correct meter sockets to measure amps. Connect the black
lead to the machine frame. Reconnect the power cord. Use the probe on the red lead to
ground PJ26, pin 7 to ground, through the multi-meter. When the LEDs CR27, CR28 and
CR29 are flashing, press and release the on / off switch and remove the probe. The
LEDs, CR12, CR13 and CR15 are ON and stay ON.
Y N
Set the service multi-meter to measure volts. Ensure the meter leads are connected
to the correct meter sockets to measure volts. Measure the voltage at the harness of
PJ26, pin 7, Flag
Y N
Check that the F1 fuse on the IOT PWB has not failed. Go to
cuits before a new IOT PWB is installed,
Install a new LVPS and base module,
PL 1.10.
Set the service multi-meter to measure volts. Ensure the meter leads are connected to the
correct meter sockets to measure volts. Measure the voltage at PJ25, pins 1 and 2,
5. +24V is measured.
Y N
Measure the voltage at the harness of PJ26, pin 9,
A B
May 2013
2-51
Flag
8. The LED CR36 is on.
01C AC Power RAP.
8. The LEDs, CR12, CR13 and CR15 are on and stay
GP 7. If necessary, install a new on / off
8.
PL 1.10 Item 3.
PL 1.10 Item 3.
IOT PWB Diagnostics RAP before a new IOT PWB is installed,
2.
24. 0V is measured.
PL 1.10 Item
PL 1.10 Item 3.
Flag 24. 0V is measured.
24, PJ27 Flag 25 and
PL 1.10 Item
Flag 24. +1.16V is
Flag 24. Press the
01H +24 Volt Cir-
2.
Flag
Status Indicator RAPs
01H