Train doors at rear M1 car not proven closded. TC opened and closed few times to no avail. Pax disem barked at BNL1 and withdrawn to UPD. ~~~~~ 1505 train doors not proven closed. TC opened and closed few times to no avail. Pax disembarked at BNL1 and withdrawn to UPD. (L3)    L3 1505 checked for FOD & air leakage from door manifold/actuator - Not found. Function check door operation ok. Postulate FOD dislodge on B side doors. Side finding: Check and found #1505 A3 door failed 10mm door gauge test. Re-adjusted door plunger & function check 10mm/20mm door gauge test - OK.  Au TK 44668