4-2 Sun Ultra 60 Service Manual • August 2001
4.1 Power-On Failure
This section provides examples of power-on failuresymptoms and suggested
actions.
Symptom
The system unit does not power up when the keyboard power switch 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 cordis
properlyconnected to the system unit and to the wall receptacle. Verify that the wall
receptacle is supplying AC power to the system unit.
Pressthe 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 switch 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. Ifthe system unit powers on, no further action is required. If the system unit
does not power on, the keyboard may be defective.Connect a spare Sun Type-5
keyboard to the system unit and press the power-on key.
If the wall receptacle AC power has been verified, the CPU module is properly
seated, and a spare Sun Type-5keyboard has been connected to the system unit and
the power-on key has been pressed but the system unit does not power up, the
system unit power supply may bedefective. See Section 4.4, “Power Supply Test” on
page4-5.
Symptom
The system unit attempts to power up but does not boot or initialize the monitor.