Lexmark C78x User Manual

2-88 Service Manual
5061
HCIT inoperative
Before proceeding with this service check, make sure the 2000-sheet tray option is properly connected to AC
power. The printer power cord plugs into the HCIT AC outlet, and the power cord from the HCIT plugs into the
AC voltage source.
Note: Make sure the electrical outlet is working properly and all power cords are plugged in correctly. Make
sure the slide switch on the LVPS is toward the right.
The system board status LED can be observed by removing the rear cover. The LED is mounted on the HCIT
system board.
Step Actions and questions Yes No
1 Does the printer power up and work normally when
plugged into the AC outlet on the HCIT?
Go to step 2 Go to step 5
2
Check the system board LED. Is it is on solid or
blinking?
• On solid means that the HCIT has detected the
front door or side door open.
• Blinking means that the system is operating.
Is the LED on solid or blinking?
If the LED is on
solid, check the
front and side
doors. If the LED
is blinking,
replace the HCIT
system board.
Go to step 3
3
Measure the voltage at TP3 (+5 V dc test point) on the
HCIT system board. The voltage should measure
approximately +5 V dc.
Is the voltage correct?
Replace the
HCIT system
board.
Go to step 4
4
Measure the voltage at CN2 pin 2 on the HCIT system
board. The voltage should measure approximately +5
V dc.
Is the voltage correct?
Replace the
HCIT system
board.
Go to step 5
5
Check the AC line voltage at the input to the LVPS.
Is the voltage correct?
Replace the
HCIT LVPS.
Go to step 6
6
Check the AC cable from the HCIT AC inlet to the
LVPS.
Are the cables good?
Determine where
the AC line
voltage is being
lost to the HCIT.
Repair as
necessary.
Replace the
cables.

Lexmark C78x Specifications

General

Brand	Lexmark
Model	C78x
Category	Printer
Language	English