U3020AS62
Service Information
Troubleshooting
This section contains information for troubleshooting the Test Set to the assembly level only. By
following these procedures, you may determine if the power supply, front panel, or main switch
board needs replacing. Refer to
If you need to disassemble the instrument, be sure to work at an antistatic
workstation and use a grounded wrist strap to prevent damage from
electrostatic discharge (ESD).
Front Panel Instrument State LEDs
If you suspect a problem with the Instrument State or Input Port LEDs, first refer to the status
definitions in
before proceeding. Note that with only a power cable
connected to the rear panel of the Test Set, the PWR LED = Green and LAN LED = Red.
1. If the green PWR LED is OFF after depressing the front panel button continue with the
following procedure:
a. Remove the top cover of the instrument.
b. Ensure that the ribbon cable and 2-wire connector are properly in place.
c. Measure the DC voltage between the red and black wires. The red wire should measure
approxi12 Vdc.
d. If the +12 Vdc is not present on the red wire, measure the three labeled output power
supply voltages on the controller module at the green connector.
e. If any voltages are not present, the controller module power supply will need to be
replaced.
2. If the green PWR LED is 'ON' after depressing the front panel button and the LAN LED is OFF,
continue with the following procedure:
a. Remove the top cover of the instrument.
b. Ensure that the ribbon cable and 2-wire connector are properly in place.
c. Measure the DC voltage between the red and black wires. The red wire should measure
approxi12 Vdc.
d. If any voltages are not present, the controller module power supply will need to be
replaced.
Keysight U3020AS62 User's and Service Guide
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