Pulse oximetry modules · Medley family

Alaris Medley SpO2 Module 8220 Masimo: troubleshooting and error codes

The ServiceForge knowledge base holds 7 documented symptoms for the Alaris Medley SpO2 Module 8220 Masimo, with 7 ranked causes, 5 diagnostic checks with test points and expected values, and 13 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Bad Sensor patient safety

Broken, unknown or nonsystem sensor or patient cable attached.

Ranked causes

1. Incorrect or incompatible sensor attached (common)

First check

Verify sensor type matches module requirements

Test point: Sensor connection
Expected: Correct system sensor attached

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Bad sensor detected patient safety

Alarm indicates broken, unknown or nonsystem sensor or patient cable attached; visual display and symbol shown when audio alarm is silenced

Ranked causes

1. Incorrect or incompatible sensor attached (common)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Check Sensor - Electrical or Optical Interference

External interference detected on sensor signal.

Ranked causes

1. External electromagnetic or optical interference (occasional)

First check

Inspect sensor for damage or contamination

Test point: Sensor condition
Expected: Clean, intact sensor with proper connection

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Check Sensor - Light

Light interference detected on sensor.

Ranked causes

1. Ambient or external light exposure on sensor (common)

First check

Assess lighting conditions at sensor site

Test point: Sensor location
Expected: Minimal direct or ambient light exposure

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Check sensor - light interference

Light interference on sensor detected; visual alarm indication displayed

Ranked causes

1. Light interference on sensor (occasional)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Check Sensor - Low Perfusion patient safety

Patient's low perfusion has inhibited monitoring.

Ranked causes

1. Poor blood perfusion at sensor site (occasional)

First check

Evaluate perfusion at current sensor site

Test point: Sensor location
Expected: Adequate pulsatile blood flow visible or palpable

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Check Sensor - Low Signal I.Q. patient safety

Low signal quality being measured by the sensor.

Ranked causes

1. Incorrect sensor placement or poor perfusion (common)

First check

Verify sensor placement per product instructions

Test point: Sensor application site
Expected: Sensor positioned correctly on well-perfused patient site

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Error codes

Code	Meaning	Trigger	Severity
`Bad Sensor`	Broken, unknown or nonsystem sensor or patient cable attached	Detection of incompatible or defective sensor or patient cable	warning
`Check Sensor - Electrical or Optical Interference`	External interference on sensor	Detection of electrical or optical interference affecting sensor signal	warning
`Check Sensor - Light`	Light interference on sensor	Detection of excessive ambient light affecting sensor readings	warning
`Check Sensor - Low Perfusion`	Patient's low perfusion has inhibited monitoring	Detection of insufficient blood perfusion at sensor site	warning
`Check Sensor - Low Signal I.Q.`	Low signal quality being measured	Low quality signal detected during pulse oximetry measurement	warning
`High Pulse Rate Alarm`	High pulse rate alarm limit has been exceeded.	Pulse rate exceeds configured alarm limit	warning
`High SpO2 Alarm`	High SpO2 alarm limit has been exceeded.	SpO2 value exceeds configured alarm limit	warning
`Low Pulse Rate Alarm`	Low pulse rate alarm limit has been exceeded.	Pulse rate falls below configured alarm limit	warning
`Low SpO2 Alarm`	Low SpO2 alarm limit has been exceeded.	SpO2 value falls below configured alarm limit	warning
`No Sensor`	Sensor not properly attached to patient cable or patient cable not properly attached to SpO2 Module.	Sensor or cable connection lost or not detected	error
`No Signal`	Failure to find a patient signal after 30 seconds of searching.	No detectable pulse signal within 30 seconds of sensor application	error
`Remove Module (Max=1)`	More than 1 SpO2 Module attached.	Multiple SpO2 modules connected simultaneously	error
`Sensor Off`	Sensor not properly attached to patient.	Sensor connection to patient lost or not detected	error

Likely causes and actions for each code are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.