Step 1520-1; Step 1520-2; Step 1520-3 - IBM RS/6000 44P 270 Service Manual

Step 1520-1

You might have been directed to this MAP for several reasons:
1. There is no indication of activity when the power-on switch on the operator panel is
pressed. None of the power LEDs light and none of the fans, including the fan in
the power supply, start to turn.
Go to "Step 1520-2".
2. When the power-on switch on the operator panel is pressed, the system begins to
power on, but the operator panel power LED and/or the power supply LED does not
stay on.
Go to "Step 1520-5" on page 47.

Step 1520-2

1. Unplug the power cord from the system unit and the power outlet.
2. Check that the external power cord to the system unit has continuity.
3. Check that the power outlet has been wired correctly with the correct voltage.
4. Plug the power cord into the system unit and the power outlet.
Did you find a problem?
NO
YES

Step 1520-3

1. Unplug the power cord from the system unit.
2. If you have not already done so, remove the covers as described in "Covers" on
page 226.
3. Press and hold the power-on switch on the operator panel for a few seconds to
discharge the power supply.
4. Unplug the power connectors (P1, P2, P3, P4, P5 and P6) from the power supply.
5. Plug the power cord into the system unit.
6. A small dark-colored switch is located on the back of the power supply, near the
back of the system. It is a normally off momentary switch. Press and hold this
switch for a few seconds while observing the fan in the power supply and the power
LED on the power supply.
Does the fan in the power supply turn on and the power LED on the power
supply change from blinking to solid while you hold the switch? (When you
release the switch, the system will power down.)
NO
YES
46
Service Guide
Go to "Step 1520-3".
Correct the problem. Go to "MAP 410: Repair Checkout" in the RS/6000 and
Eserver pSeries Diagnostics Information for Multiple Bus Systems.
Replace the power supply. Go to "Map 0410: Repair Checkout" in the RS/6000
and Eserver pSeries Diagnostics Information for Multiple Bus Systems.
Go to "Step 1520-4" on page 47.