More than a dozen subway lines are experiencing delays throughout the transit system Tuesday morning, with problems ranging from mechanical issues, signal glitches and pulled train brakes, the MTA said. 

Customers on the 4, 5, 6, B, D, F, M, G, J, Z, N, Q, R and W were all seeing slowdowns during their morning commute as of 9:30 a.m. 

The 6 trains in both directions and southbound 4 and 5 trains are running with delays after the MTA said it addressed a mechanical problem on a train at Grand Central-42 St. 

Meanwhile, northbound B, D,and Q trains are running with severe delays after multiple incidents, including a customer activating a train’s brakes and EMS assistance being requested for a passenger earlier Tuesday at Cortelyou Rd. A signal problem also activated a train’s brakes earlier at 59 St-Columbis Circle, the MTA said. 

F and G trains are running with delays in both directions while the MTA addresses a signal problem near Bergen St. 

J and M trains are also running with delays in both directions after MTA crews moved a train that had its brakes activated at Essex St. 

Southbound N and W trains are running with delays after the MTA addressed a train with a mechanical problem at Queensboro Plaza, the transit agency said.