Replacing The Main Logic Board - Sun Microsystems SPARCstation 2 Service Manual

4

Replacing the Main Logic Board

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This section explains how to replace the main logic board into the system unit.
To replace the main logic board:
1. Insert the connectors on the rear of the replacement board into the back
panel as shown in Figure 4-26.
2. Align the board so that the five tapered mounting holes align with the
standoffs in the bottom of the chassis.
After the board is properly aligned, slide it back toward the rear bezel until
the standoffs lock into the mounting holes.
3. Install two Phillips head screws to secure the main logic board to the rear
of the chassis (see Figure 4-26).
4. Connect the 12-pin power cable from the power supply to connector J0701
(see Figures 4-25 and 4-26) in the right front corner of the main logic
board.
5. The connector is keyed so that the power cable will fit only one way.
6. Connect the 34-line diskette drive data and power cables to the connectors
on the main logic board (see Figure 4-26).
The data cable connector is J0501 and the power connector is J0704 (see
Figure 26).
7. The connectors are keyed so they will fit only one way.
8. Connect the hard disk drive data and power cables to the data and power
connectors on the main logic board (see Figures 4-25 and 4-26).
Drive 1 data cable is J0402, and drive 1 power cable is J0703. Drive 2 data
cable is J0401, and drive 2 power cable is J0702
9. The connectors are keyed so that they will only fit one way.
10. Connect the LED/Speaker cable assembly to connector J0602 in the right
front corner of the main logic board (see Figures 4-25 and 4-26).
11. Re-install the SIMMs into their original sockets.
See "SIMMs" earlier in this chapter for the correct locations.
SPARCstation 2 Field Service Manual—February 1991