An electrical connection testing system for testing existence of an electrical connection between a first electronic device and a second electronic device. An electrostatic discharge (ESD) protection circuit is provided between the first and second electronic devices. The testing system includes a comparator having a first input connected to a power for output of the first electronic device and a second input connected to an output signal from the first electronic device. The output signal is adapted to be sent to the second electronic device through the ESD protection circuit. The testing system also includes a system for determining if a comparator output from the comparator is indicative of the first and second inputs being different or if the comparator output is indicative of the first and second inputs being substantially the same.