Troubleshooting AEDS

AEDs are rugged, low maintenance and easy to use. However, things don’t always go to plan, so it is important to be aware of the following problems and fixes.


Failed Operation

The most common problem with AED operation is the way in which pads are attached to patients. Always check the pictures on each pad to make sure you place them in the right position, and always make sure that the pads are not touching. Poor pad connection can interrupt ANALYSIS and prevent a SHOCK being delivered, so it is important to have good pad-to-patient contact. Wipe all moisture off the skin and shave any excessive hair. Press the pads firmly to the patient’s chest and check their connection to the AED. If the unit still fails to work, the pads themselves may be damaged or out-of-date, so they will need to be replaced.

Patient movement can affect the operation of an AED, so there may be times when you need to move a patient to a more stable location (if possible). If you are transporting a patient, you may need to stop the vehicle during ANALYSIS.

Another common problem with AED operation is battery life. If a unit’s operating time is short and it turns off during use (or won’t turn on), the battery needs to be replaced, recharged or conditioned. If this problem persists, the unit needs servicing.

Extreme temperature can affect the operation of an AED. Most units are designed to operate between 0 and 50 degrees Celsius, and while Tasmanian temperatures rarely fall outside this range, there may be times when you encounter a patient in cardiac arrest in extreme weather. If this happens, you will need to move the patient to a more favourable operating temperature (if possible).

Electrical interference can sometimes cause an AED to not operate correctly. If this happens, you need to remove the source of the interference.

Finally, some problems are not problems at all. If an AED is operating but the screen is too dark or light, you simply need to adjust the screen contrast.


If an AED unit is not working properly, report the fault to supervisor and arrange to have it serviced. Do not attempt to repair faults yourself!

IDevice Icon Troubleshooting AEDS Gallery
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troubleshooting AEDs
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pictures on pads
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pad placement
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change battery
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change battery

Want to Learn More?

If you are interested in learning more about operating AEDs, take some time out to browse the following online medical reference site:

Note: this is an external website. If you click on the above link, you will leave the Cardiac Arrest with AED eLearn course for Volunteer Ambulance Officers (VAOs) site.


If you are interested in reading and learning more about cardiac arrest and defibrillation, go to the Skills Sheets and Essential Reading sections. If you would like to check your understanding of this eLearn course, go to the Assessment section.

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