Agilent Technologies 6632B, Service Manual

Page: 25 / 83

Troubleshooting - 3
25
Turn on unit and observe the
display. Unit should display all of
the segments and annunciators,
the address and then after self
test display either an error
message or go to the metering
mode.
Protect
Annunciator
On?
Display comes
on?
A3J2-5 held
low?
Yes
Replace A2
Interface board
No
No
+5V @ A3J2-8?
Troubleshoot A1
+5V Interface Bias
circuit, W6 or W7.
No
Yes
RI?
Replace A3 Front
Panel/Display
board
Error Message?
See Error Message
Table 3-2
Yes
Yes
No
OV?
No
OC?
No
Go to
"Troubleshooting
OV at Turn-on"
(sheet 4)
Yes
Check RI input, A2
Interface board
Yes
Disable OCP and
check for normal
operation
Yes
Replace internal
fuse F300
Go to sheet 2
No
FS?
No
For OT check fan
circuit, thermal
sensor RT301
No
Fuse blown?
Yes
Yes
Go to "FS indicated
but fuse is OK"
(sheet 6)
No
Figure 3-1 Sheet 1. Main Flowchart