As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO PLATFORM DUE TO A MESSAGE IN EICAS AND STATUS OF AUTO BRAKES AND BRAKE CONTROL WERE SHOWN. MAINTENANCE PERFORMED THE FIM DMC-B787-A-32-40-F2-34A-421A-A PROCEDURE, SHOWING FAILURE CODE BRAKES 42-01863, AUTOBRAKE 32-30530 AND BRAKE CONTROLS 42-01863. THE BRAKE SYSTEM CONTROL UNIT WAS REPLACED IAW AMM DMC-B787-A-32-42-03-01A-520A/720A-A, TESTED CORRECT.