DNAinfo/Nicole Bode
UNION SQUARE — The MTA is investigating whether Friday's sweltering heat caused a mechanical failure on the downtown 6 train.
Southbound 6 trains were diverted to the express track at the 14th Street-Union Square Station due to failure of the platform's mechanical gap filler, an MTA spokesman said.
Straphangers who need a downtown local 6 train will have to board on the station's express 4/5 track, the spokesman added.
The spokesman said it was not yet known if heat had caused the breakdown.
