Service manual

4-1
CHAPTER
4
Troubleshooting Procedures
This chapter describes how to troubleshoot possible problems and includes
suggested corrective actions.
■ Section 4.1 “Power-On Failure” on page 4-1
■ Section 4.2 “Video Output Failure” on page 4-2
■ Section 4.3 “Hard Drive or CD-ROM Drive Failure” on page 4-3
■ Section 4.4 “Power Supply Test” on page 4-4
■ Section 4.5 “DSIMM Failure” on page 4-8
■ Section 4.6 “OpenBoot PROM On-Board Diagnostics” on page 4-10
4.1 Power-On Failure
This section provides examples of power-on failure symptoms and suggested
actions.
Symptom
The system unit does not power up when the keyboard Power-on key is pressed.
Action
Check the keyboard connection. Ensure that the keyboard is properly connected to
the system unit. Check the AC power cord. Ensure that the AC power cord is
properly connected to the system unit and to the wall receptacle. Verify that the wall
receptacle is supplying AC power to the system unit.
Press the power switch. If the system unit powers on, the keyboard may be defective
or the system unit is unable to accept the keyboard power-on signal. Power off the
system unit and press the keyboard Power-on key again. If the system unit powers
on, no further action is required. If the system unit does not power on, the CPU
module may not be properly seated. Inspect the CPU module for proper seating. If