Chapter 3. Maintenance Analysis Procedures (Maps); Map 1520: 7012 G Series System Unit - Power Map - IBM 7012 G Series Service Manual

Chapter 3. Maintenance Analysis Procedures (MAPs)

MAP 1520: 7012 G Series System Unit - Power Map

Note: This is not a start of call MAP. Use this Power MAP only if you have been directed
here from a MAP step in the Diagnostic Information For Micro Channel Bus
Systems .
This procedure is used to locate power problems in 7012 G Series system units. If a
problem is detected, this procedure helps you isolate the problem to a failing unit.
Note: If you need more detailed information about the Power/Keylock Status Register
(PKSR) bit definitions when using this map, see Error Logging, on page D-26. A
detailed description of the system power states can be found in "Appendix E.
System Power States."
Observe the following safety notice during service procedures.
Note: For a translation of these notices, see System Unit Safety Information .
DANGER
An electrical outlet that is not correctly wired could place hazardous voltage
on metal parts of the system or the products that attach to the system. It is
the responsibility of the customer to ensure that the outlet is correctly wired
and grounded to prevent an electrical shock.
Before installing or removing signal cables, ensure that the power cables for the
system unit and all attached devices are unplugged.
When adding or removing any additional external devices to or from the system,
ensure that the power cables for those devices are unplugged before the signal
cables are connected. If possible, disconnect all power cables from the existing
system before you add a device.
Use one hand, when possible, to connect or disconnect signal cables to prevent
a possible shock from touching two surfaces with different electrical potentials.
During an electrical storm, do not connect cables for display stations, printers,
telephones, or station protectors for communication lines.
CAUTION:
This product is equipped with a 3-wire power cable and plug for the user's safety.
Use this power cable in conjunction with a properly grounded electrical outlet to
avoid electrical shock.
Maintenance Analysis Procedures (MAPs)
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