Updated for 7.0
Click on the Settings icon (the gear) located to the right of the search bar. This will take you here:
In the horizontal navigation bar, select Accounting. From the drop down, select Payment Types. This will take you here:
Within the Payment Types box, locate eCheck. To the right, use the On/Off toggle to turn eCheck’s On/Off.
Then, select the green button titled Update at the bottom of the Payment Types box.