Sun Microsystems 1.0, Service Manual

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Wear a grounding wrist strap when handling the boards. Attach the wrist strap to
the metal casing of the power supply at the rear of the unit top. Handle boards only
by the edges. Do not touch the components themselves or any metal parts.
Do not disconnect the power cord from the system unit power outlet or from the
wall socket. This connection provides the ground path necessary to safely remove
and install the printed circuit boards and components. In addition, keep the internal
power supply cable connected to the MLB.
Make sure that the system unit power is turned OFF by checking that the green
light-emitting diode (LED) at the front of the chassis is not lit and the fan in the
power supply is not running.
1. Check that the green LED at the front of the chassis is not lit.
2. Check that the system power cord remains connected to the system and the
wall outlet.
3. Remove the system unit’s cover.
Refer to “Removing the System Unit Cover” on page 32 in Chapter 4.
4. Attach the wrist strap.
Refer to “Attaching the Wrist Strap” on page 34 in Chapter 4.
Caution -
Hot surfaces are present. Use care when opening the system chassis or
handling components.
5. Push back both card retainers for the MBus module.
If the system has two MBus modules (slot 1 on top of slot 0), and slot 0 is the
defective module, remove the top module first. See Figure 9–1.
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SPARCstation 10 Service Manual
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Revision A, July 1993