TC reported TIMS showedfront DT B4 door obstacle detected. Fault self cleared after train doors cl osed. ~~~~~ T217 3626 TC reported TIMS showed front DT B4 door obstacle detected. Fault self cleared after train doors closed. Reported at CBR NB CE checked:3626 B4 door intermittent door operation problems Some station able to open some unable to open  Found #3626 B4 door RHS outer roller damaged. Replaced both LHS and RHS door rollers with iron roller and function test/static test/cyclic test ok. Done by: Kumar/Yusof. 11.7.24