NELLCOR PURITAN BENNETT Symphony N-3000 Service Manual page 60

Section 5: Troubleshooting
5.6.4 Display/Alarms
5-8
Table 5-5 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 5-5: Display/Alarms Problems
Condition
1. Display values are
missing or erratic.
2. Display segments do
not light.
3. Alarm sounds for no
apparent reason.
4. Alarm does not sound. 1. Verify the problem with the service mode
Recommended Action
1. If the sensor is connected, replace the sensor
connector assembly.
2. If the condition persists, replace the sensor
extension cable.
3. If the condition does not change, replace the
SpO PCB.
2
4. If the condition still persists, replace the UIF
PCB.
1. Verify the problem with the service mode
menu item 2, knob and lamp test.
2. Check the connection between the UIF PCB
and the Display PCB.
3. If the condition does not change, replace the
Display PCB.
4. If the condition still persists, replace the UIF
PCB.
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.
menu item 4, speaker test.
2. Replace the speaker as described in Section 6,
Disassembly Guide .
3. If the condition persists, replace the UIF PCB.