Really sorry, I just grabbed the wrong page. Here is the page for the 5400
Entering Diagnostics Mode
1. Make certain the printer is OFF.
2. Press and hold buttons [2] and [6] on the Control Panel while you switch ON
printer main power. Continue holding until *IOT?* appears in the display
(approximately 20 seconds).
3. When the Control Display shows *IOT?*, release buttons [2] and [6] and press
button [4]. The Control Panel first reads “Entering IOT Diagnostics Mode” then
changes to “Main Menu, Component Test.” The printer is now in Diagnostics
Mode.
Note: You must press button [4] within 10 seconds after *IOT?*
appears in the display to enter Diagnostics Mode, or the
printer will default to a normal power-up sequence.
Note: If you miss the 10-second window, the printer will reenter its
normal boot sequence. To try again, power down the printer,
wait 20 - 30 seconds, and begin at step 1 above again.
4. Diagnostics Mode menus are navigated like On Line Mode menus. Use buttons [1]
and [5] to display the three top level menus, Component Test, Test Print and NVM
Config. When “NVM Config” is displayed and you push buttons [2] or [6] to reach
the NVRAM submenus, “Enter Password” will be displayed. Sequentially press
[0], [7], [3], [4] to gain entry.
5. To exit Diagnostics, you must switch printer power OFF for 10 seconds, then
switch printer power ON for normal operation in the On Line mode.
"Impatience will reward you with dissatisfaction" RMS Cosmics'97