Paramedics have been given instructions on how to deal with potential faults, however, the procedure can take up to 5 minutes to complete.
Concerns have been raised by some ambulance workers after a piece of life-saving equipment failed during a recent emergency call-out.
A number of the cardiac devices been removed from service following an error message during call out in south Leinster.
Paramedics have since been given instructions on how to deal with potential faults, however, the procedure can take up to 5 minutes to complete.

Ryanair Boss Stands By His Comment Comparing Other Airlines To Rapists
The European Central Bank Announces Interest Rate Increases
Gardaí And Europol Investigate Horse Trafficking In Kildare And Other Counties
Vice Chair Of Kildare Club Believes GAA Are "Seriously Lacking Leadership"
Kildare Highlighted As Having Highest Suicide Rate In Ireland
Four HSE Regions Lose Power Over Day-To-Day Spending
Harris Prepares For First Budget As Finance Minister As FG Think-In Takes Place
Bord Gáis Energy Announce Price Rise