Agilent Technologies 16900A

28 16900A, 16902A, and 16903A Service Guide
5 Troubleshooting
Figure 2 16900A and 16902A Power Troubleshooting Flowchart
2
Remove power plug for 15 seconds
to reset power supplies.
Apply power.
Are the
fans turning &
power on?
1
Yes
Are power supply
voltages correct?
Replace the
defective
power
supply.
No
Are the
MIB green/yellow
LEDs on? (see
pg 38)
Module interface board is detecting a
bad voltage. Green indicates 500 watt
supply. Yellow indicates 700 watt
supply. Go to 'To check the power
supply voltages' in this chapter.
Is there
a power
short?
Replace the
damaged
assembly.
Replace the
MIB (module
interface
board).
Yes
The power down signal is
asserted from CPU or MIB.
Check the CPU power cable
and the reset cable. Check the
AUX +5V power. Go to 'To
troubleshoot power problems' in
this chapter.
Replace the CPU.
Replace the MIB.
No
Is the
module interface
board's red
LED on?
No
Check for a power short, burnt
components, traces, etc.
No
The over-temperature
circuit is tripped.
Is the
instrument at room
temperature?
Let it cool and
check for fan
failure.
Replace the MIB (module
interface board).
No
Yes
Yes
YesYes
No
B
C
A
A B C
Try , then , then .
Return to between each.
2