9870 grain loss monitor trouble

I have an 08 9870 that the grain loss monitor isn't working correctly on. When the center readout comes up neither the Chaffer or rotor loss monitors come up any. (One bar on eAch is all that's illuminated). I can't fine tune my machine for loss when I don't know what area it's being lost from. The center. Seems to work accordingly to what grain I'm finding on the ground

9870 grain loss monitor trouble