Power On Sequence Troubleshooting; Check The Line Voltage And Fuse; Check The Power Supply Unit Output - Keysight Technologies E4981A Service Manual

Power On Sequence Troubleshooting

Check the Line Voltage and Fuse

Check the main power line cord, power fuse, and actual line voltage to see that they are all
correct. For more information about the line cord and power fuse, see the Power
Requirements in Appendix B.

Check the Power Supply Unit Output

Step 1. Remove the E4981A's outer cover.
Step 2. Turn the E4981A power on.
Step 3. Check the output voltage (+3.3 V and +5 V) of the power supply unit. LED on A31 board
are turn on with green if the power unit is worked correctly. The location of LED on the
A31 board is shown in
Figure 4-2 Output Voltage Location
Chapter 4
Power On Sequence Troubleshooting
Figure 4-2.
Troubleshooting
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