Stepping Motor Issue

Apologies if this is in the wrong location.

A while ago I bought a few of the 28BYJ-48 stepping motors from eBay, as I already had one from a kit that worked fine. The ones I purchased all came with a slightly different controller board using the ULN2003 chip. There are 8 input pins IN1 / IN2 / IN3 / IN4 / VM / VCC / VCC / GND but it does not have any of the LEDs to show the steps being pushed through.

No matter what I have tried I cannot get this to work.

In the end I took apart my old project to get the controller board from that, plugged it in and then it worked straight away.

The attached image shows the controller on the right I cannot get working (tried two and different wires etc.) the one lit up is obviously all working.

Nothing complicated, all I was trying to do was get the motor rotating at a constant speed.

Any help would be appreciated as I will look to see if I can buy these LED lit boards on their own for the motors I have.

Paul

Did you common Vcc and Vm on the board to 5V? Are there any resistors on the ULN2003 inputs or do you have to provide those yourself?

The ULN2003 needs resistors on the inputs or it could burn up (or burn up your Arduino pins), and the Vcom pin must be connected to the motor common positive lead so the internal diodes can act as free-wheel diodes and prevent high voltage spike damage.