Train doors at car 3685 A2 were not proven closed. TC opened and closed a few times to clear fault. to clear fault. ~~~~~ 3685 A2 Train doors were not proven closed. TC opened and closed a few times to clear fault. Fault recurred at MRB NB. TC opened and closed a few times  to clear fault.  685/686 ER D/L - Done. Checked 3685 A2 door for any FOD - Not found. Door function test - OK. Cleared J-rail & adjusted sensor s/w 0.5mm closer. Push/pull gauge test before cleaning 6kgf, after cleaning 4kgf. Door operation cyclic test 10 times - OK.  Selvan/Lee PT 44106