Table 8: Display/Alarms Problems - Nellcor OxiMax N-550 Service Manual

Display/Alarms
N-550
Table 8 lists symptoms of problems relating to non-functioning displays and
audible tones or alarms and recommended actions. If the action requires
replacement of a PCB or module, refer to Disassembly Guide on page 55.

Table 8: Display/Alarms Problems

Symptom
Display values are
missing or erratic.
Not all display segments
light during POST.
All Front Panel LED
indicators do not light
during POST
Alarm sounds for no
apparent reason.
Display is flashing, but
there is no alarm.
Recommended Action
Try another sensor or relocate the sensor.
Replace the Sensor Extension Cable.
Replace the sensor.
Replace the Front Panel PCB. See Front Case
Disassembly on page 58.
Check the connection between the Front Panel PCB
and the Main PCB.
Replace the Front Panel PCB. See Front Case
Disassembly on page 58.
Check the connection between the Front Panel PCB
and the Main PCB.
Replace the front case. See Front Case Disassembly
on page 58.
Moisture or spilled liquid can cause an alarm to sound.
Allow the N-550 to dry thoroughly before use.
Replace the Front Panel PCB as described in Front
Case Disassembly on page 58.
Verify that alarm silence has not been activated. See
Menu Item 12 (Silence Alarms) on page 40.
Check speaker connection to Front Panel PCB. Refer
to Front Case Disassembly on page 58.
Replace the speaker. Refer to Front Case Disassembly
on page 58.
Replace the Front Panel PCB. Refer to Front Case
Disassembly on page 58.
Troubleshooting
47