Normally there are two air lines to the VH5C. One is for the collet closer and the other is for the brake. The solenoid on the back of the controller is probably for the brake. When it is controlled by the machine an M60 and M61 are used
to operate the brake. What you may need is an air line to the regulator and another to the solenoid to supply pressure for the brake.
Hope this helps.