The E-DC does not have a enable/disable input. However the Remote input allows the user to mimic a shutdown. This input allows you to reduce current to a motor from a remote location. Reducing the current to zero allows you to mimic a shutdown, with zero current your motor should not have holding torque.
Remedies
Connect pins 16 and 17 or use your Parker Stepper cable.
EDC DRIVE I/O CONNECTOR
To reduce motor current to zero, short the CURRENT and REMOTE terminals together (with a wire). When the remote input is enabled, the open collector transistor internally connected to the REMOTE screw terminal will conduct to ground.
EDC REMOTE and CURRENT