PRINTER TECH ARTICLE
4250/4350 Formatter, DC Controller Installation
The 4250, 4350 and 4240 print at different speeds, yet are essentially identical machines. In par- ticular, the DC controller is the same and non-base models use the same formatter. These two boards house memory chips that store a printer's identity, page count and menu settings. Thus, a 4350 prints at 55 pages per minute because its "memory tags" say it can.
This setup is generally convenient. When you have to replace either board, the printer automati- cally copies all the information to the new board us- ing the unreplaced board as a source. Manual page count reentry is thus unnecessary.
On the other hand, not following the correct pro- cedure could result in loss of the identity tag, which could change your 4350 into a slower 4250.
Replacing the Formatter or DC Controller for the 4250/4350/4340
cold reset paper size, and the serial number. But in our experiments, these items got copied over from the other board even when performing the NVRAM initialization procedure.
After it reaches the “Ready” state, wait five min- utes, then turn the printer off and on. During the five-minute wait, do not use the printer menus.
After it reaches the “Ready” state, wait another five minutes.
Print a configuration page to verify all information has been copied into the NVRAM on the new board.
Ordering the right part
Formatter, base models: Q3653-67904
Formatter, network models: Q3652-67905
DC controller: RM1-1108
IF REPLACING BOTH BOARDS, follow the steps first for the formatter, then repeat them for the DC controller.
1. Power off the printer, remove all accessories and network cards, and disconnect it from comput- ers and networks.
2 . I n s t a l l t h e b o a r d
Turn the power on, wait for the memory count to begin, and then press and hold the “Down Ar- row” button.
After all three control-panel lights flash once and then remain on (this should take about 10 sec- onds), release the “Down Arrow” button.
Press and release the “Up Arrow” button.
Press and release the “Menu” button. The dis- play should show “SKIP DISK LOAD”.
Press the “Up Arrow” button until “NVRAM INIT” is highlighted.
Press the “check mark” key. The printer will perform the NVRAM initialization procedure and then continue with its normal power-on se- quence. HP claims that you will now have to go into the service menu and specify the total page count, the maintenance count, the service ID, the
NVRAM chips on the DC controller and the formatter record the iden- tity of the printer model and all par- ticular information about the printer, including page counts.
SERVICE EDGE, WINTER 2011 For printer info, one site: lbrty.com