What was found
DURING TRANSIT CHECK, THE MESSAGE IN EICAS AND STATUS OF THE STAB L2, CABIN AIR CPRSR L-2, FMC CHANNEL C AND STABILIZER LIGHT TURNED ON WERE SHOWN. MAINTENANCE PERSONNEL FIM 27-40 TASK 801 PROCEDURE AND AMM DMC-B787-A-27-40-F1-01A-421A-A, DMC-B787-A-21-50-F1-88A-421A-A AND DMC-B787-A-21-50-F1-88A-421A-A, NO CONFIRMING FAILURE AND THE MESSAGES DISAPPEAR. LEFT ELECTRO-MECHANICAL CONTROL UNIT WAS REPLACED IAW AMM DMC-B787-A-27-41-08-00A-520A-A AND AMM DMC-B787-A-27-41-08-00A-720A-A, TESTED CORRECT.