TC reported TIMS showed obstacle detected at car 2602 'B4' door. Fault recur at subsequent stations.Staff(RFP) checked and confirmed car 2602 'B4' door did not opened. Subsequently isolated car 2602 "B4" door in closed ~~~~~ 2602 TC reported TIMS showed obstacle detected at B4. Fault recur at subsequent stations. Staff(RFP) checked and confirmed 2602 'B4' door did not  opened. Subsequently isolated 2602 "B4" door in closed position.  2602 B4 door no FC recorded. #2602 B4 door unable to open. Checked/found #2602 B4 door RHS outer rollerdelaminated,LHS-OK. Replaced RHS door outer roller. Cleaned J-rail/guide rail & no FOD was found. Door gap 63.7mm, weather strip condition, door cyclic test, door open/close timing - OK. All doors proven closed & no DIR lit up.  Sarma/Alan/Aliff 45130