Power Checkout; Recovering Bios - IBM 8645 - Eserver xSeries 220 Hardware Maintenance Manual

Power checkout

Power problems can be difficult to troubleshoot. For instance, a short circuit can
exist anywhere on any of the power distribution busses. Usually a short circuit will
cause the power subsystem to shut down because of an overcurrent condition.
A general procedure for troubleshooting power problems is as follows:
1. Power off the system and disconnect the AC cord(s).
2. Check for loose cables in the power subsystem. Also check for short circuits, for
3. Remove adapters and disconnect the cables and power connectors to all
4. Reconnect the AC cord and power on the system. If the system powers up
To use this method it is important to know the minimum configuration required
for a system to power up (see page 117).

Recovering BIOS

If the BIOS has become damaged, such as from a power failure during a flash
update, you can recover the BIOS using the flash ROM page-swap jumper (J38)
and a BIOS flash diskette.
Note: You can obtain a BIOS flash diskette from one of the following sources:
The flash memory of your server consists of a primary page and a backup page.
The J38 jumper controls which page is used to start the server. If the BIOS in the
primary page is damaged, you can use the backup page to start the server; then,
start the BIOS flash diskette to restore the BIOS to the primary page.
To recover the BIOS, do the following:
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Hardware Maintenance Manual: xSeries 220 Type 8645
instance if there is a loose screw causing a short circuit on a circuit board.
internal and external devices until system is at minimum configuration
required for power on (see "Minimum operating requirements" on page 117).
successfully, replace adapters and devices one at a time until the problem is
isolated. If system does not power up from minimal configuration, replace
FRUs of minimal configuration one at a time until the problem is isolated.
v Use the ServerGuide program to make a BIOS flash diskette.
v Download a BIOS flash diskette from the World Wide Web. Go to
http://www.ibm.com/pc/support/, select IBM Server Support, and make
the selections for your server.
1. Turn off the server and peripheral devices and disconnect all external cables
and power cords; then, remove the cover.