Sun Microsystems SPARCclassic Service Manual page 77

Halt the system and verify that the power LED is not lit and that the fan is not
running. Then open the system unit and attach a wrist strap as described in
"Attaching the Wrist Strap" on page 53.
Caution - The AC power cord should remain attached between the system unit and
an AC wall outlet. This connection provides the ground path necessary to protect
internal system components from harmful static discharges. Inside the system unit,
be sure the power supply wiring harness is connected to the main logic board to
complete the ground.
Caution - Verify that the system power switch is in the Standby position. The green
LED at the front of the system unit should not be lit and the fan should not be
running. When the system power switch is in the Standby position, and the AC
power cord remains connected to a power outlet, hazardous AC voltage is still
present in the power supply primary. Do not attempt to service the power supply
under these conditions. Disconnect the AC power cord prior to handling the power
supply. When servicing any other system component, the AC power cord should
remain connected and poses no safety hazard.
2. Disconnect the speaker/LED cable from its connector on the main logic board.
For the connector location, see Chapter 11.
3. Squeeze the speaker assembly where indicated in Figure 8–2 and slide it up
and out of the system unit.
Caution - Do not touch or press on the speaker cone. You may damage the speaker
or the sound quality.
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Major Subassemblies