Video Output Failure - Sun Microsystems Ultra 80 Service Manual

Action
Ensure that the keyboard is properly connected to the system. Ensure that the AC
power cord is properly connected to the system and to the wall receptacle. Verify
that the wall receptacle is supplying AC power to the system.
Press the power switch. If the system powers on, the keyboard may be defective
or the system is unable to accept the keyboard power-on signal. Power off the
system and press the keyboard power switch again. If the system powers on, no
further action is required. If the system does not power on, the CPU module(s)
may not be properly seated. Inspect the CPU module(s) for proper seating. If the
system powers on, no further action is required. If the system does not power on,
the keyboard may be defective. Connect a spare Sun Type-6 keyboard to the
system and press the power key.
If the wall receptacle AC power has been verified, the CPU module(s) is properly
seated, and a spare Sun Type-6 keyboard has been connected to the system and
the power key has been pressed but the system does not power up, the system
power supply may be defective. See Section 4.5 "Power Supply Troubleshooting"
on page 4-6.
Symptom
The system attempts to power up but does not boot or initialize the monitor.
Action
Press the keyboard power key and watch the keyboard. The keyboard LEDs
should light briefly and a tone from the keyboard should be heard. If a tone is not
heard or if the keyboard LEDs do not light briefly, the system power supply may
be defective. See Section 4.5 "Power Supply Troubleshooting" on page 4-6. If a
keyboard tone is heard and the keyboard LEDs light briefly but the system still
fails to initialize, see Section 3.8 "Initializing Motherboard POST" on page 3-42.
4.3

Video Output Failure

This section provides video output failure symptom and suggested action.
Symptom
No video at the system monitor.
Action
Ensure that the power cord is connected to the monitor and to the wall
receptacle. Verify that the wall receptacle is supplying AC power to the monitor.
Check the video cable connection between the monitor and the system graphics
-4 Sun Ultra 80 Service Manual • March 2000