3.14 How to Replace the Main Logic Board

3.14.1 Before You Begin

All removable components should have been removed from the old main logic board prior to removing the board from the system. You can transfer the components to the replacement board after it is installed in the system. For more information, see:

• "3.13 How to Remove the Main Logic Board"

Use an antistatic mat when working with the main logic board. An antistatic mat provides the cushioning required to protect the board, to prevent the main logic board from flexing, and to provide antistatic protection.

Perform this procedure on a workbench. Sun Microsystems does not support changing the main logic board while the system is installed in a rack.

Do not attempt to install components on the main logic board while it is outside the system. Doing so can damage the main logic board.

Be sure to complete this task before starting the procedure:

• "2.1 How to Power Off the System"

3.14.2 What to Do

1. Remove the main logic board from its antistatic packaging and place it on an antistatic mat.

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   Caution -

   Handle the main logic board by the back panel or edges only.

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2. Set the jumper settings on the replacement main logic board so that they match the jumper settings on the original main logic board.

   See "3.15 How to Set the Serial Port Jumpers" and "3.16 How to Set the Flash PROM Jumpers".

3. Position the replacement main logic board in the chassis.

   Align the notches on the sides of the board with the corresponding tabs on the chassis.

   

4. Slide the main logic board toward the back of the system.

   Ensure that each connector on the main logic board slides through the corresponding cutout in the chassis back panel.

5. Replace the three screws securing the main logic board to the system back panel.

6. Connect the following internal cables to the main logic board.

   The connectors are keyed to connect in only one way. For information about cable connector locations, see "5.5 How to Connect the System Cables".

   1. Connect the main power cables to connectors J2902 and J2903.

   2. Connect the CPU power sense cable to connector J2901.

   3. Connect the UltraSCSI data cable to connector J1801.

3.14.3 What Next

Complete these tasks to reassemble the system:

• "3.8 How to Replace the NVRAM/TOD Module"

• "3.12 How to Replace the CPU Card Cage Assembly"

• "3.10 How to Replace the Air Guide"

• "3.6 How to Install a CPU Module"

• "3.2 How to Install a Memory Module"

• "3.4 How to Install a PCI Card"

• "2.7 How to Replace the System Cover"

When you are ready to restart the system, be sure to run OpenBoot Diagnostics tests to verify that the system functions correctly with the parts you have just installed. For additional information, see:

• "7.6 How to Use OpenBoot Diagnostics (OBDiag)"

You may also have to perform a reconfiguration boot so that your system is able to recognize any new parts. For additional information, see:

• "2.3 How to Initiate a Reconfiguration Boot"