OOZNest Volt Meter Not Functioning

I've finished building the OOZnest CNC PSU and discovered that the voltage meter is not working.

I live in the United States, so before plugging in the power cord, I set the input voltage switch on the side of the PSU to 115V. I then plugged the power cord into the unit's IEC-Inlet and then into my wall socket. I turned on the switch to the IEC-Inlet and the indicator light comes on. The cooling fan also turns on as well as an LED light on the circuit board next to the voltage adjustment screw. The LED-Volt-Meter does not light up. I turned off the overhead room lights to see if maybe it was just a dim display. I also turned the voltage adjustment screw both ways to its endpoints and still no display on the LED Volt-Meter.

After turning the unit off and pulling the plug, I removed the LED Meter from the PSU cover to check my wiring sequence. I have the red wire running to the left most screw terminal and the black wire running to the fourth screw terminal from the left end. I have the screws going through the terminal plates first (grooved side up) and then through the ring terminals.

I also removed and reattached the LED Meter wires from their terminal connections to rule out connection problems.

The only thing I can think of is that I purchased a power cord for the unit because the kit came with a European cord and plug. The cord I purchased from a computer store is a three prong grounding plug with a rating of "Max. 10A 125V".

Any suggestions would be greatly appreciated. I am a novice when it comes to electrical wiring and have no electrical diagnostic tools.

Thanks for the help!

 

Ryan:
I did as you suggested and cut off the factory supplied ring terminals, stripped about 3/4" from the two wires insulation, wrapped the bare wire around the terminal screws and reattached the screws to the PSU as usual. I turned on the power and everything works fine! Thank you for your prompt response to my inquiry. It gives me great comfort knowing that OOZnest stands behind their high quality product with high quality customer service!