Fifteen subway lines to be impacted this weekend

It may be a little tricky for straphangers to get around this weekend.

Fifteen of the MTA's 21 subway lines will be affected by maintenance or construction work, the agency said Thursday. The only routes not affected by service changes are the A, B, E, Z and No. 1 trains.

Among the diversions this weekend, the Knickerbocker Avenue M stop in Bushwick will be shut down in both directions for five months starting Saturday so workers can refurbish the station. Construction will be done at four other stations along the line over the next year.

Also, countdown clocks along the MTA's numbered subway lines were out of service for a few hours on Thursday as federal officials tested the system.