I am a non-railroader curious about operation of the locomotive independent brake when the cab car is controlling. I assume there is an independent brake valve in the cab car (but no J-1 Relay), and that both the actuating line and the independent application and release line are carried through the train from loco to cab car (along with the brake pipe and the main reservoir line. The whole setup is then equivalent to MU operation of several locomotives as far as control of the loco's independent brake is concerned. Am I correct?
at least on MN there is no independent brake on cab cars or controlled by cab car.
its train brake or no brake at all.