Pax feedback 2nd last pair of train doors did not open. Staff(KRJ) checked and confirmed no abnormal ities found in opening and closing of the train doors. ~~~~~ 3669 Pax feedback 2nd last pair of train doors did not open.    Staff(KRJ)checked and confirmed no abnormalities found in opening and closing of the train doors. CE: 3669 B2 door found intermittent fault during opening, When closing - ok.  3669 B2 door found slow when closing, no FC was recorded. Checked door rollers condition - OK. No FOD was found. Cleaned J-rail/guide rail & No FOD was found. Weather strip condition & door gap 63.9mm. Swapped DCP from #3669 B2 door to #3669 A2 door. Function check & found A2 door slowing in closing. Replaced #3669 A2 DCP. Function check door open/close operation - OK. All doors were proven closed & no DIR lit up. Door open/close timing - OK.  Sarma/Alan/Aliff 45133 DCP S/N : (after swapped) #3669 B2 : 1601W020001S028 #3669 A2 : 1701W020071S029 (NEW) #3669 A2 : 1701W020031S024 (Faulty)