Service Guide
39
Verifying main board CPU operation
1.
If the printer does not power up (rear fan is off and power-up
diagnostics LEDs are off), go to the topic, “Verifying power supply
operation” below.
2.
Observe the rear panel LEDs located on each side of the rear panel DIP
switches.
The left LED represents the operation of the PostScript firmware.
The right LED represents operation of the main board’s print engine firmware.
During the POST tests the two LEDs toggle back and forth for each
successful pass through each DRAM test. A failure in the power on self
tests is indicated by the left LED (the PS led) flashing in a specific
pattern of long and/or short flashes and repeated indefinitely. Other
failures are indicated by the failure being printed on the Startup page.
After successful power-up, the left LED flashes at a regular “heartbeat” rate. The
front panel
Power
light is turned on, the
Error
light is flashed, and the LCD is
cleared.
Verifying print engine operation by printing its startup page
1.
If not already on, turn on the printer. If the printer does not begin
initializing, go to the topic, “Verifying power supply operation” below.
2.
Once the
Power
light is on (not blinking) and the front panel displays
Ready to Print
, scroll to
Menu
and press
Select.
Then scroll to the
Printer Configuration menu item, press
Select,
and then scroll and
select the
Startup page
menu item
.
The printer should print out a
Startup Page.
If the printer prints a startup page, then the print engine is working correctly. If
the printer does not print a startup page, then a problem exists with the print
engine.
Verifying power supply operation
The power supply is divided into two sections: the AC section used for heaters
and the DC section for control logic, printhead drivers and motors. Verifying the
power supply involves three steps:
■
Checking for proper AC voltage.
■
Inspecting the power supply fuses.
■
Testing for a shorted motor or solenoid driver, which shuts down the
power supply.
Required tools
■
TORX T-20
screwdriver
■
Digital multi-meter (DMM)
Summary of Contents for Phaser 840
Page 46: ...36 Phaser 840 Color Printer ...
Page 95: ...Service Guide 85 Clearing PostScript NVRAM menu item ...
Page 96: ...86 Phaser 840 Color Printer ...
Page 121: ...Service Guide 111 Figure 1 Cabinet FRUs 7 5 6 8 1 2 4 0388 21 3 ...
Page 125: ...Service Guide 115 Figure 3 Paper path FRUs 0388 16 2 1 5 11 10 9 12 6 4 3 7 13 8 ...
Page 127: ...Service Guide 117 Figure 4 Motors and fans FRUs 0388 14 7 4 3 5 6 2 1 ...
Page 129: ...Service Guide 119 Figure 5 Circuit boards FRUs 4 3 5 2 1 9 7 6 8 10 11 13 0388 13 12 ...
Page 131: ...Service Guide 121 Figure 6 Solenoids and clutches FRUs 4 5 3 2 1 0388 23 ...
Page 137: ...Service Guide 127 Figure 9 High capacity PaperTray 0388 65a 1 2 ...
Page 142: ...132 Phaser 840 Color Printer ...
Page 154: ...144 Phaser 840 Color Printer ...