Bought a LCTHC from Viper Plasma and Can't get this thing to work. I hooked it up as the manual says and can't get the test mode to do anything. I removed all the wiring to the THC and ran power only to the unit and it behaves the same way. You go to run the test but it flickers where the ref Voltage should be. If I wait long enough I can get the ref voltage to display properly or if I disconnect the THC wire the Ref voltage shows up. What do you guys think?