Replaced Extruder Motor With 0.9 Degree Stepper. Won't turn

I wanted to do a bit of a rebuild on my Folger Tech FT-5's extruder setup, and I figured I'd swap out the motor for one with a higher resolution than the stock 1.8 degree motor. The motor I selected was this one from AliExpress, and I tested it out with an external driver that I use for a turntable and it ran just fine with the 12V from a lead-acid battery as the power source. When hooking it up to the printer, however, the motor jolts a little bit at the start of a move action, and then it's just silence. No further turning, noise, or torque. The driver in the printer is the same as the one on my turntable, and I already fiddled with the current potentiometer, but nothing causes to motor to react at all. Plugging in the old motor shows that the driver still works.

I'm stumped as to what could be causing this. Perhaps it's the really long cable run going to the stepper (1.5-2 meters), perhaps it the 1/16th microstepping that's hard-wired to the drivers, maybe it's the voltage rating of the motor, but I can't think of anything definitive that would be fixable. Any help would be greatly appreciated.

TL;DR and other information:
-Swapped stock 1.8 degree extruder motor for 0.9 degree in a MK10 direct-drive extruder
-It will not turn, but the driver still works with the old motor
-The new motor turns with the same type of driver on a test rig
-The main control board on the FT-5 is the MKS Gen1.4
-The stepper drivers are A4988 Stepper Drivers
-Problems may be due to microstepping, long cable length, and/or motor voltage.

Motor specs as listed on AliExpress:

• Rate Phase Voltage: 2.8V
• Current/Phase: 1.68A
• Inductance/Phase: 3.2mH
• Holding Torque: 3.3kg*cm
• Number of phases: two

Edited 1 time(s). Last edit at 03/10/2018 12:18PM by Lazerlord.

This could be a polarity issue with the motor. Bipolar Nema 17 motors have 2 different coils and each coil has a positive and negative side, hence the 4 cables that are required to make it work. In some motors the poles are side to side, in some others they might be spaced apart. Any easier way to imagine this is by illustrating it:

Let's name the poles: A and B for the positive and negative sides of the first coil and C and D for the positive and negative sides of the second coil. Your cables can be arranged as follows:

ABCD or ACBD

If your mainboard's pin arrangement requires an ABCD configuration, the ACBD form won't work. So you need to convert it to ABCD. Easiest way to do it is to remove the middle pins from the Dupont connector (or whatever connector you have) and swap them. That way, you will have an ABCD arragement. Be careful with the Duponts or other connectors though, thay have very small tabs which can be broken easily.

A practical way to determine the poles is to use a LED. Put the LED's legs on two of the connectors and manually turn the motor in both directions. If the LED lights up, then you have found a couple (There is a risk that you can burn the LED if the voltage is too high).

Edited 2 time(s). Last edit at 03/11/2018 09:53AM by drmaestro.