#3720, DURING PM, SELF TEST FAILED,TO ~~~~~ #3720, DURING PM, SELF TEST FAILED, 3720 conducted self test a few times to no avail. 3720 conduct parking brake test/ service brake test according 6MCE01, check physically service and Parking thread brake unit no sign of air leak. Brake cyclic observed 3720 BC1 and BC2 abnormal at TIMS. Check using Digital pressure gauge at EP2002 Gateway Valve and RIO valvesimilar pressure as on TIMS. Refer below 3720 bogie 1(Gateway Valve) AS-3.08 Coast-0 B1-1.71 B2-2.42 B3-2.44 EM-2.85, 3720 bogie 2(RIO Valve) AS-2.79 Coast-0 B1-0.23 B2-0.17 B3-0.21 EM-2.55 Swap 3720 RIO valve to 3719. Conduct self test fail at 3719. Fault Transfer Awaiting spare RIO valve Ops20 to replace at 3719 Checked by Koh/Saini/Haslan/Haikel/Din. 17/6/21 Awaiting spare RIO Valve 3719 as fault transfer        #3719 RIO V/V change out done.Brake function ok.Self test both cab ok. RIO v/v: Old s/n: 1743075SPC   Newc s/n: 1805104SPS Not: 2288101 Raise. Done by Sanip/Koh. 21/06/21 ,,,,