Section 5: Troubleshooting
5-4
5.6.2 Buttons
Table 5-3 lists symptoms of problems relating to nonresponsive buttons and
recommended actions. If the action requires replacement of a PCB, refer to
Section 6,
Disassembly Guide
.
Table 5-3: Button Problems
Condition
Recommended Action
1. The NPB-190 responds
to some, but not all
buttons.
1. Replace Top Housing assembly.
2. If the buttons still do not work, replace the UIF PCB.
2. The NPB-190 turns on
but does not respond to
any of the buttons.
1. Check the connection between the membrane panel
and J5 of the UIF PCB.
2. Replace Top Housing assembly.
3. If the buttons still do not work, replace the UIF PCB.
5.6.3 Display/Alarms
Table 5-4 lists symptoms of problems relating to nonfunctioning displays,
audible tones or alarms, and recommended actions. If the action requires
replacement of a PCB or module, refer to Section 6,
Disassembly Guide
.
Table 5-4: Display/Alarms Problems
Condition
Recommended Action
1. Display values are
missing or erratic.
1. Try another sensor or relocate the sensor to a
different site.
2. If the sensor is connected, replace the sensor
connector assembly.
3. If the condition persists, replace the sensor
extension cable.
4. If the condition still persists, replace the UIF
PCB.
2. All display segments
do not light during
POST.
1. Check the connection between the UIF PCB and
the Display PCB.
2. If the condition does not change, replace the
Display PCB.
3. If the condition still persists, replace the UIF
PCB.
3. All Front Panel LED
indicators do not light
during POST.
1. Check the connection between the membrane
panel and J5 of the UIF PCB.
2. Replace Top Housing assembly.
4. Alarm sounds for no
apparent reason.
1. Moisture or spilled liquids can cause an alarm to
sound. Allow the monitor to dry thoroughly
before using.
2. If the condition persists, replace the UIF PCB.
