TC reported TIMS showed obstacle detected at Front M2 car 'A4' door. Fault self-cleared and did not recur at subsequent stations. Staff(SBW) checked the train a nd confirmed Front M2 car 'A4' door did not open at station ~~~~~ 2656 TC reported TIMS showed obstacle detected at A4 door. Fault self-cleared and did not recur at subsequent stations. Staff(SBW) checked the train and confirmed Front M2 car 'A4' door did not open at station platform.  2656 A4 door FC 076 (Saloon door A4 com Error 6) & FC 070 (Com Fault). Checked/found A4 LHS outer door rollerdelaminated. Replaced the delaminated roller. FOD found: N Weather strip & roller condition ok: N (LHS door outer roller                                            delaminated) Clean J-rail & guide rail: Y 10/20mm gauge test pass: Y Push/pull gague test pass: Y Door gap: 63.5mm Door cyclic test: 20x TIMS door static timing test pass: Y Cleaned J-rail as preventive measure. Door cyclic test - ok.  Sarma/Alan/Lee PT/Anand 45208