P
AGE
52
Trouble-shooting
and Diagnostics 5.4
This section consists of two columns. The first column is a list of some possible instrument
conditions. The second column is a list of steps that should improve the condition. The steps
should be performed in order until the condition improves or all the steps have been tried. If
the instrument condition has not improved, contact the nearest representative or the factory
for assistance.
Trouble-shooting should be performed by qualified personnel using the proper equipment and
following all safety precautions. Whenever possible, the trouble-shooting should be accom-
plished with the electrical power disconnected. The instrument contains static sensitive
components so care should be taken to observe anti-static procedures.
Condition
Correction Steps
Display is blank (dark)
1. Verify that the correct instrument power, as
indicated on the wiring label on the housing, is
supplied to terminals A & B. If the voltage is not
correct, check the power source.
2. Turn off the instrument power. Wait about 5
seconds, then turn the power on again.
3. Turn off the instrument power, loosen the front
panel screw, and remove the instrument from the
housing. Inspect the instrument for poor
connections.
a. The white ribbon cable that connects the
Processor board (Appendix A-2, page 60)
to the Power Supply Board (Appendix A-
1, page 59) must be properly aligned
and seated.
b. The Front Display board pins should be
properly aligned and seated in the
sockets on the Processor board
(Appendix A-2, page 60) and the
Power Supply board (Appendix A-1,
page 59).
c. The Display Driver (U-1), located on the
Display board, must be free of corrosion
and firmly seated in the socket. Reinsert
the instrument in the housing, tighten the
panel screw, and turn on the power.
4. Turn off the instrument power. Press and hold the
UP and DOWN keys. Turn on the power. Hold
the keys depressed for about 10 seconds. If the
display lights the model number, Program and
Tune mode parameters will need to be re-entered
(page 28 & 33 or the Software Ref. Sheet, page
70, if already filled out).
Model Number Displayed
1. Turn off the instrument power, wait 5 seconds then
is incorrect
reapply the power. Verify that the number dis-
played during the power up sequence is the same
as indicated on the label affixed to the lower front
of the display bezel.
