Technical data

9050 Diagnostics 5-7
Normal Operation Sequence
Normal
Operation Indication
What Normal Indicates Probable Failure
Power On IB LED on. AC to Main Power Supply
Power On switch.
AC power cable.
Fuse.
Self-Tests
(Board).
Self-Test
(Boot
Loader)
OTLEO off.
Stack PS LED
off.
Power On LED
on.
Fans operating
Self- Test LED
on. Stack
LEOs
on for l/Z second
then
off.
Stack board
LEOs remain off.
Temperature in stack and
Main PS is in tolerance.
Voltages on stack
PS are in
tolerance.
Main
PS and Stack PS vol-
tages are
in tolerance.
Both power supplies operat-
ing
and in tolerance. Fans and
drivers are good.
Primary Power On signal is
good.
SCM initiated self-test signals.
Motherboard/SCM connec-
tions.
Stack
LEOs and drivers are
good.
Stack boards are good.
LEOs on 110 card 110 cards are good.
remain
off.
110/220 switch.
Interlock switch not engaged.
Stack
PS to Main PS cable discon-
nected.
Temperature
Filter screen clogged.
Fans.
Stack
PS board.
+ 19 volts or -12 volts to the Stack
PS.
Short on a Stack PS output.
Main Power Supply.
Stack
PS.
Short on one of the Power Supply
outputs.
Main
PS.
Stack PS.
Fans.
Fan cables.
SCM.
SCM.
SCM/Motherboard connector J4 and
J5.
LED.
Stack board.
Motherboard.
Stack board (LED that's on).
Stack board (LED that's lowest
in
group).
SCM clock (1M RAM LED not blink-
ing during test, or
all stack boards
failed test).
CPU (all LEOs on).
110 card (with LED lit).
Load LED on.
Boot loader loading into
RAM SCM board.
Motherboard.
I/O cable.
Start of boot loader self-tests.
SCM board.
110 card cage 110 card cage LEOs are good.
LEOs on for l/Z
second.
Motherboard.
LEOs.
SCM board.
Motherboard.
lOP Cable.