As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APPLIED POWER TO AIRCRAFT AND VERIFIED THE #1 ADC SHOWS AS FAILED. PUSHED THE SELF TEST BUTTON ON FRONT OF UNIT, NO SIGN OF SELF TEST WAS SEEN. REMOVED #1 ADC UNIT AND VERIFIED POWER AND GROUNDS TO UNIT. ALL POWER AND GROUNDS CHECKED GOOD.