HP Integral Personal Computer Service Manual page 146

Integ,.. ......... , Com ...... ' Troubl.shootlng and D'.gnostics . 8-83
Table 8·27. Trouble.hooting Setup
This
table gives the procedure to set up the computer for troubleshooting the logic A and logic B
PCAs. As you proceed with the steps below, refer to chapter 6 ·Removal and Replacement' for the
correct disassembly procedures .
• To troubleshoot the logic A PCA, perform steps 1 through 4.
• To troubleshoot the logic B PCA, perform steps 1 through 6 .
• lep
1. Turn off the
pow~r
and remove the power cord.
2. Remove the back cover from the computer
(if
you have not already done
so).
3. Remove the operating system ROM assembly and install the service ROM assembly if you have
not already done so. (Exception: Leave the operating system ROM installed if you are using the
built-in printer diagnostic tests.)
4. Remove the metal shield to uncover the logic A PCA.
In this configuration
you
can troubleshoot the logic
A peA.
S. Remove the six screws that hold the PCA mounting panel. Tilt the panel down and toward you
(unhook the cable clip from the printer-mechanism cables). Support the panel to prevent any
strain on the cables (see figure 8-10).
I. Now uncover the logic B PCA as follows: Remove the four screws holding the logic B shield.
Carefully lift the shield, without detaching the display and printer cables. Support the shield in
an upright pOSition with the printer cable clip (see figure 8-10) so that it will not fall on the
PCA (possibly causing a short).
In this configuration you can troubleshoot the logic B PC.4.
• . . . > ••
~
......... . , . . ,
~
_ _ _ _ Logic 8 PCA
..... ltI
:-..;! ...
t---- ......
8 PCA
Figure 8·10. Troubl •• hooting Setup