Instrument Self-Test; Table 3-2 Instrument Self-Test Troubleshooting - Keysight 8990B Service Manual

Instrument Self-Test

Table 3-2 Instrument self-test troubleshooting
Sel f-test
Test point voltages
Fan
Battery
PLL
Channel 1 measurement path
test
Channel 1 memory interface
test
Channel 4 measurement path
test
Keysight 8990B Service Guide
Purpose
Ensures that all the supply
voltages are present
Verifies that the fan
is working
Ensures that the lithium
manganese battery on the
main board is working
Ensures the connectivity
between the scope acquisition
board, DAP, filter board, and
DAP board
Ensures that the measurement
path of channel 1 is working
Ensures that the memory
interface of channel 1
is working
Ensures that the measurement
path of channel 4 is working
Debug tip
Replace the PSU
Unplug and plug back the fan
assembly and the main board
Replace the battery
Unplug and plug back the
cable connection between the
acquisition board and DAP
filter board
Replace the DAP board
Replace the DAP board
Replace the DAP board
Troubleshooting Guide
Possible faul ts
– Main board (high
probability)
– PSU (low probability)
– Fan assembly (high
probability)
– Main board (low probability)
– Lithium manganese battery
(high probability)
– Main board (low probability)
– DAP filter board (high
probability)
– Test acquisition board
1 GHz or DAP board (low
probability)
– DAP assembly (high
probability)
– Main board or channel 1
sensor adapter board (low
probability)
– DAP assembly (high
probability)
– Main board (low probability)
– DAP assembly (high
probability)
– Main board or channel 4
sensor adapter board (low
probability)
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