If it's the Aquacomputer USB D5 Pump then it needs to be powered with a 12v Molex connection & you'll need to have it connected also by the USB, So... Just connect Via the Molex & USB first (do not connect it via the Aquabus yet) to begin with to check it has the most upto date firmware & I would set the "Control Priority" to USB.. Although really I think it should run even if it's just connected to the Molex alone, It should run at it's factory set Default speed. So maybe try that first just to make sure the pump is running/working?.
If you have the pump connected via the aquabus & have not set up a "Controller" setting for it from the Aquasuite main menu it doesn't know how or when to run.
If it won't run when connected with just the Molex connection then it does sound like the pump may be faulty....
Have a look
HERE I've done a review & set up guide for the D5, It may help

....
Good luck
N.