Printer Rear Assemblies; Engine Control Board; Engine Driver Board - Tektronix Phaser 550 Service Manual

8
FRU Disassembly/Assembly

Printer rear assemblies

Engine control board

Engine driver board

8-14 Phaser 550 Color Printer
Note
If you are removing the engine control board or the engine driver
board to access an assembly underneath, it is appropriate to
disconnect the board's wiring harnesses and then remove the board
and its mounting bracket as an assembly.
1. Remove the upper rear cover as explained in the earlier procedure,
"Upper rear cover" on page 8-2.
2.
Disconnect the wiring harnesses leading to the engine control board.
3. Remove the four screws securing the board in place. Remove the
engine control board by pulling it straight out, unplugging it from the
engine driver board. (Upon reassembly, securely tighten the screws.)
4. To remove the engine control board bracket, remove the four screws
securing the bracket in place.
Note Swap NVRAM IC2. This IC stores print engine parameters the
needed gamma correction. Also, when adjusting gamma, and
correction does not product a noticeable change then it is possible that
the NVRAM is damaged.
Connectors CN15 and CN10 have no corresponding plugs. These
two connectors are for development purposes only.
1. Remove the upper rear cover as explained in the earlier procedure,
"Upper rear cover" on page 8-2.
2. Remove the engine control board and bracket as explained in the
previous procedure.
3.
Disconnect the wiring harnesses leading to the engine driver board.
4. Remove the five screws securing the board in place. Remove the
engine driver board. (Upon reassembly, securely tighten the screws.)
5.
To remove the engine driver board bracket, remove the four screws
securing the bracket in place.
Note When installing a new board ensure that DIP Switch SW301, switch
four (4) is in the up position, and that all other switches are down.
This allows the print engine to read the Gamma Correction Density
from the print engine control board NVRAM (IC2).