You may have a negative degree of superheat or subcooling
Subcooling is not working-
1)Plug in thermocouple into LLT port and change refrigerant to R113 to check to see if the manifold calculates subcooling.
Superheat is not working-
1)Plug in thermocouple into LLT port and change refrigerant to R407F to check to see if the manifold calculates superheat.
