Nonin Onyx II 9590

Battery Not Charging or Power Failure

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Asset Type

Pulse Oximeter

Manufacturer

Nonin

Model

Onyx II 9590

What This Guide Helps With

Device will not power on, shuts off unexpectedly, or shows no response due to battery depletion or charging-related issues.

Step-by-Step Troubleshooting

Ensure Patient Safety First

Verify the Reported Issue

Check Battery Installation and Type

Replace Batteries with Known Good Set

Inspect Battery Contacts

Check for Physical Damage or Moisture Exposure

Test Power Button Function

Attempt Multiple Power Cycles

If the Problem Persists

If the device still does not power on after verifying batteries, contacts, and external condition, the issue is likely internal (power circuit or board failure).

Remove the device from service, label it Out of Service, and send for repair or bench evaluation.

Knowing when to stop prevents unnecessary time spent on non-serviceable internal failures.

Clinical Use Tip

Do not troubleshoot a pulse oximeter on a patient. Always move the patient to a working device before beginning troubleshooting.

Work Order Documentation (CCR Method)

CCR = Complaint, Cause, Resolution

Complaint

What was reported by the clinical staff.

Example:
"Pulse oximeter would not power on during patient use."

Cause

What was observed during troubleshooting.

Example:
"Batteries depleted and battery contacts slightly corroded."

Resolution

What action was taken.

Example:
"Replaced batteries and cleaned contacts; device powered on and passed functional check."

Helpful Details to Include (If Known)

Final Thought

Power issues on handheld devices are most often simple battery or contact problems. Start with these basic checks before assuming failure. Patient safety comes first, and proper escalation ensures efficient use of time and resources.

That is successful troubleshooting.

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