On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
This guide helps troubleshoot Error 120.4320 High voltage on 24V supply line, which indicates an overvoltage condition on the internal power rail. This can cause the pump to shut down, fail to power correctly, or create unsafe charging behavior.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Stop the infusion and remove the pump from patient use
- Transfer therapy to a functioning pump
- Confirm patient care continues without interruption
Verify the Reported Error and Behavior
- Power on the pump in the module or PCU
- Confirm Error 120.4320 is displayed
- Determine when the error occurs (docking, AC connection, or during operation)
- Observe whether the module powers at all
- Check if the issue only occurs when connected to the PCU
Check PCU (Point-of-Care Unit) Power Source
- Ensure the PCU is plugged into a known good outlet
- Verify the PCU powers on normally
- Check if other modules are experiencing similar power issues
Test Module in a Different PCU Slot or Another PCU
- Move the affected module to a different slot in the same PCU
- Test the module in a known working PCU
- Observe whether the error follows the module or remains with the PCU/slot
Inspect Module and PCU Connectors
- Check connectors for bent pins, debris, or contamination
- Look for signs of arcing or discoloration
- Reseat the module securely
Remove from Dock and Test Standalone (If Applicable)
- Undock the module and observe behavior if standalone function is possible
- Determine if the error only occurs when docked
Check for Environmental or Physical Damage
- Inspect for liquid intrusion
- Check for burning smells or excessive heat
- Look for cracks or physical damage to the housing
If the Problem Persists
If Error 120.4320 continues after external troubleshooting and isolation:
- Internal power regulation circuitry (module or PCU) is likely faulty
- Overvoltage conditions cannot be safely corrected externally
- Remove the affected equipment from service
- Label the device as Out of Service
- Send the module and/or PCU for repair based on isolation results
Clinical Use Tip
Never troubleshoot an Alaris pump on an active patient. Always transfer the patient to a backup device before performing any troubleshooting steps.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Alaris module displaying Error 120.4320 and not operating when connected to PCU."
Cause
What was observed during troubleshooting.
Example:
"Overvoltage fault persisted across multiple PCUs and slots, indicating internal module power regulation failure."
Resolution
What action was taken.
Example:
"Tested module in multiple PCUs, confirmed fault followed module, removed from service and sent for repair."
Helpful Details to Include (If Known)
- Alarm behavior
- Accessories swapped
- Power behavior
- Environmental factors
- Indicator lights
- Final device status
Final Thought
Power-related errors in Alaris systems require careful isolation between module and PCU. Always verify external sources first, but escalate quickly when overvoltage conditions persist to ensure safety and reliability.
That is successful troubleshooting.