As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. WHILE ACCOMPLISHING TASK CARD 78L00000027 AIRCRAFT WOULD NOT ALLOW EMERGENCY LIGHTS TO GO IN SLEEP MODE WITH CFMS. MASTER PRIME WIRELESS CONTROL UNIT WOULD NOT ALLOW TEST. REPLACED WIRELESS CONTROL UNITS 13 (AALA202010279026) AND 27 (AALA202010289004), PER AMM DMC B787-A-33-51-07-01B-720A-A. A SATISFACTORY BITE AND OPERATIONAL CHECK WAS PERFORMED.