Hey there! When dealing with a malfunctioning Edwards EST SIGA-HFD device, there are a few potential causes to consider. Firstly, ensure that the device is properly powered and connected to the system. Check for any loose wiring or connections that might be interrupting the signal. Additionally, verify that the device itself is not physically damaged or obstructed in any way. If everything appears to be in order externally, it’s possible that there could be a fault with the device internally, requiring either repair or replacement. I’d recommend starting with these steps and if the issue persists, contacting technical support for further assistance.