HP (Hewlett-Packard) LJ 4000T Printer User Manual


 
114 Chapter 2 Service mode EN
To gain access to Diagnostic mode
1 Unplug (or turn off) the product from the power source.
2 Press and hold down V
OLUME, STOP/CLEAR, and 1 on the one-touch
keypad simultaneously.
3 Continue to hold down the buttons while you plug back in (or turn
on) the product, through the entire power-on sequence.
The table below shows the tests and button sequences to perform in
Diagnostic mode.
To perform this test Press these buttons
Toggle LED1 on/off
1 or 5 on the one-touch keypad
Toggle LED2 on/off
2 or 6 on the one-touch keypad
Access LCD pattern 1
(solid fill)
1 on the numeric keypad, <, or >
Access LCD pattern 2
(empty fill)
2 or 8 on the numeric keypad
Access LCD pattern 3
(> fill)
3 or 9 on the numeric keypad, or
REDUCE/ENLARGE
Access LCD pattern 4
(H fill)
4 on the numeric keypad or 3 or 7 on
the one-touch keypad
Access LCD pattern 5
(frame fill)
5 or 0 on the numeric keypad, or
RESOLUTION
Access LCD pattern 6
(check fill)
6 on the numeric keypad
Access LCD pattern 7
(ROM check)
7 on the numeric keypad or RE DIAL/
P
AUSE
Access firmware version number
#, *, or 10 on the one-touch keypad