Out of service cars can be worked in a yard or shopped, as required by the defect(s). As was pointed out, a door light problem could be worked in the yard or shopped. An A/C unit changeout or wheels to be trued of course must be shopped.
Shopped cars dp not have to go to HMC. West Side Yard has a 6 track shop, including a wheel truing machine. Ultimately, the LIRR will also be able to use it's own shop at Arch Street, once we boot Bombardier out of there. Theses shops are primarily for the electric fleet, although Hillside also does some work on the C-3, such as 3 year air brake work. There are also other shops for the diesel fleet.
The dilapidated blue barn you might see in Babylon Yard (track 10a) was a 4 car shop. 30 day PIs (Periodic Inspections) used to be done in there once upon a time. (With my seniority now, I wish it were still operative. 3 minutes from home, with traffic.) They stopped using the shop for PI some years ago, and TC - 81 was parked in there for awhile. Today, there may be a pair of M-7s in there for training. There are also some M-7 mockups in there for training. (Also a lot of pigeon droppings.
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