Train doors at car 3543 were not provenclosed. TC recycled train doors twice - ok. Fault did not re cur at subsequent stations. ~~~~~ 3543 Train doors were not proven closed. TC recycled train doors twice - ok. F ault did not recur at subsequent stations. Depot check door function.  3543 Checked all doors - No FOD. Weather strip-OK. Clean J-rail & guide rail. 10/20 mm door checked - Passed. No manifold or actuator leak. Door cyclic test, DZR able to extinguish. Door TIMS static test - within criteria. DMV - No residue voltage. Pull/push checked - OK. Postulate FOD dislodged. Lee JC 44970