Lothean:
Yes, the EN pin is held LOW, the RESET and SLEEP pins are held HIGH
I never know whether EN should be HIGH or LOW so I assume you have read the documentation 
There's just 1.3mA flowing when the voltage is around 1V at best (it fluctuates from 0 to 1V)
I don't know where, or with what you measured the voltage. I can't imagine how there could be 1V anywhere if there is a 12v power supply. Can you post a diagram showing all the circuit connections when you were measuring the current and voltage. And can you confirm that your Arduino program was not sending any step commands.
If you were doing the measurements the way I envisage them being done I would suspect a failed stepper driver.
...R