To Test The Lcd Display Signals - Agilent Technologies 1670G Series Service Manual

To test the LCD display signals

Before attempting to do this procedure, ensure that the video signal cable connected to the
LCD display and to the CPU board is properly seated in both connectors. Attempt to reseat
the cable two or three times. If other repairs were done to the instrument, and the video is
now no longer operating, it is very likely that the video cable is not properly seated at either
the LCD display or the CPU board.
Refer to chapter 6, "Replacing Assemblies", for instructions to remove or replace covers and
assemblies.
W A R N I N G
Warning Hazardous voltages exist on the power supply and the LCD display, and the LCD
inverter. This procedure is to be performed by service-trained personnel aware of the
hazards involved, such as fire and electric shock.
Remove the following assemblies. Refer to chapter 6 for more information on how
1
to remove the assemblies.
•
Cover
•
Disk Drives
•
Acquisition Board
Reconnect the power supply.
2
a. Position the power supply so that it does not obstruct the CPU board, yet provides access to
probe J4 on the CPU board.
b. Connect both the line filter and the power output cable to the power supply.
c. Ensure the power supply does not contact any other subassembly in the instrument.
Using an oscilloscope, probe the following pins of J4 for digital signals.
3
12,13,14
16,17,18
20,21,22
24,25,26
28,29,30
23,33,34
Troubleshooting
To test the LCD display signals
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