IBM RS/6000 Enterprise Server M80 Service Manual page 138

Step 1540-15
To isolate the primary I/O drawer perform the following steps.
1. Turn off the power.
2. Select fast boot mode (select enable fast boot) on the System Power Control menu from the service
processor main menu.
3. Verify that primary I/O drawer RIO port 0 is connected to CEC drawer RIO port 0.
4. At the primary I/O drawer, remove the cable connected to RIO port 1.
5. Verify that the primary I/O drawer V/S COMM port is connected to CEC drawer V/S COMM port.
6. Verify that the primary I/O drawer JTAG port is connected to the CEC drawer JTAG port.
Note: The primary I/O drawer should be cabled as shown in "Cabling the CEC Drawer, Primary I/O
Drawer, and Secondary I/O Drawer(s)" on page 46. Be sure to look at both RIO cables and
SPCN cables.
7. Disconnect ac power cables (dc power cables in a dc-powered system) from remaining I/O drawer(s).
Attention: For ac-powered systems, the rack that you are working on may have I/O drawers that are
connected to other CEC drawers or other third-party drawers attached to the power distribution unit. To
avoid removing power from drawers that are used by other systems, when you are instructed to unplug
power from an I/O drawer, remove only the power distribution unit (PDU) side of the single ac cables
connected to the I/O drawer in question.
8. All I/O drawers except the primary I/O drawer should now be physically disconnected from the CEC
drawer.
Go to "Step 1540-16."
Step 1540-16
The primary I/O drawer is the only remaining I/O drawer connected to the CEC drawer.
1. Turn on the power to boot standalone diagnostics from CD.
2. If the Please define the System Console screen is displayed, follow directions to select the system
console.
3. Use the Display Configuration and Resource List to list all attached devices and adapters (refer to the
RS/6000 and Eserver pSeries Diagnostic Information for Multiple Bus Systems if necessary).
4. Check that all attached devices and adapters are listed.
If the Please define the System Console prompt did not display or all attached devices and adapters are
not listed, the problem is in the primary I/O drawer.
Did the Please define the System Console screen display and are all attached devices and adapters
listed?
NO Go to "Step 1540-17" on page 121.
YES Go to "Step 1540-27" on page 127.
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Service Guide