NEC POWERMATE ES 5200 - SERVICE, Service Manual

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Troubleshooting 8-7
Diagnostics
One beep indicates that the system has completed its POST test. If intermittent
beeping occurs, power off the system and try again. If the beeping persists, see
the following table. The table summarizes problems that may develop during
system operation and lists (in sequential order) suggested corrective actions.
Problems and Solutions
Problem Symptom Solution
No power Power lamp on computer status
panel does not light. 1. Check that the power cord is plugged
into the power socket on the computer.
Check that the other end of the cord is
plugged into a live, properly grounded AC
power outlet.
2. Check cable connections between the
power supply and riser board and between
the riser board and power switch.
3. Systematically eliminate possible
shorted PCBs by removing cables and
expansion boards.
4. Check the +5 and +12 power supply
voltages. Measure voltages with the system
board installed.
5. Replace the power switch assembly.
6. Replace the power supply.
7. Replace the system board.
Power supply
malfunction Any of the following conditions
could occur:
Front panel lamps out, diskette
and/or hard drives do not spin,
monitor blank, interface ports not
working, and keyboard lamp out
and/or cannot input from keyboard.
1. Perform steps 1 through 4 listed in this
table under No Power.
2. Check power supply voltages. Voltages
should be measured with a load on them
(system board plugged in).
3. Replace the power supply.
Operating system
does not boot Intermittent beeping at power-on.
Computer beeps more than once
and is unable to complete boot-up. 1. Check system configuration (see
Section 2).
2. Check all jumper settings and verify that
drives are enabled (see Section 2).
3. Reseat DIMMs and option boards in
their connectors. Inspect system board for
foreign objects such as paper clips.
4. Remove option boards and reboot.
5. Replace system board.