DT Check found Car 1555 coupler heavy ai ~~~~~ 1555 DT Check found coupler heavy air leakage. (Air Leak failed - 0.8bar)  1555 found underframe MR isolation v/v slightly open due to cable conduit hitting v/v handle. Normalised MR v/v & secured cable conduit with cable tie. Further checked/found #3555 WSP test point leaking & replaced. Air leak test after rectification at 0.5 bar/5 min.  Nelson 44380