Diode D7 in CW-lite

My CW-lite’s diode D7 is on occasionally.

However, there is no description of the diode D7 in the schematic.

What does diode d7 mean in CW-lite?

D7 is “ADC lock failed”: CW1173 ChipWhisperer-Lite - NewAE Hardware Product Documentation

Its value is reflected in scope.clock.adc_locked.
Ensure that scope.clock.adc_src is set appropriately and that it identifies a valid clock (i.e. if it’s extclk*, do you have a valid clock on the HS1 pin?
If the ADC clock source has changed, you many need to run scope.clock.reset_adc() (and sometimes more than once).

Jean-Pierre