Troubleshooting Power Supplies And Interlocks; Troubleshooting Ac Power - Xerox Phaser 7700 Service Manual

Troubleshooting Power Supplies and Interlocks

Troubleshooting AC Power

1. Verify that the AC Input Voltage is present and correct.
2. Verify that the Reset button on the GFI is depressed.
3. Reconnect AC power. If the GFI trips immediately with the Power Switch off,
disconnect AC power, remove the rear cover and metal shields. Check for
shorts in the AC Circuit from the GFI to the Noise Filter, the AC Driver Board
and up to the Power Switch.
4. Switch the printer on. If the GFI trips, unplug the printer, remove the fuser,
then retest. Disconnect AC power, remove the rear cover and metal shields.
Check for shorts in the AC Circuit from the Power Switch back to the AC
Driver Board and to the bottom connector on the three Low-voltage Power
Supplies.
5. Remove the rear cover and the two metal shields. Connect AC Input and
switch the printer on. Check for AC voltage at:
J72 on top of the GFI, if not present replace the GFI.
Between FS76 and FS77 of the Noise Filter, if not present replace the
Noise Filter.
Into and out of the Power Switch, if not present replace the Power
Switch.
The connector at the bottom of the 3.3 VDC, 5 VDC and 24 VDC LVPS, if
not present replace the AC Drive Board.
Note The GFI, Noise Filter and AC Drive Board are all part of the AC
Electrical Chassis, see (RRP 49, on page 7-198).
Service Quick Reference Guide - Troubleshooting
3-87