Geeetech

I Just installed my new Printrboard and I am having some challenges. It is driving a QUBD TwoUp which is a simple Cartesian 3d printer. This printrboard replaces my my previous printrboard which was damaged when a spool of filament fell on it. Up to that point, my original board was working fine.

I installed the new board and uploaded the same firmware I used on my previous board.

Problem 1
As soon as I power up the board, the cooling fan turns on. It will not turn off using M107 command. However, once the machine moves in the z-axis, the fan will turn off. However, after 2-3 minutes the fan comes back on.

Problem 2
On my previous board, I had the stepper current tuned to 1.45v reference voltage on all my steppers. If I use that same setting on this board, my stepper motors skip or jam during a print. I can tune these down to about 1.2v, but then they seem to lose torque.

Is this something in firmware or is my board defective?

What is the version of your prvious board?

This is my original printrboard: This is the board I received from geeetech:

apologies. those were the wrong images.

This is my previous board: This is the board I received from geeetech:

Please check if this place is short circuit.

I tried to get a closeup picture but it's not clear. There does appear to be some issues around those pins. When I hold it at an angle I'm able to see a little under the pins and there may be some solder behind them that is shorting out the pins.

If you have multimeter, please check if that 2 pins are short circuit.

of course. what was I thinking.

yes! I measured all pins on the chip. there appears to be a short across 4 pins directly behind the jumper that you identified. Some of the pins are reading 0, others are reading around 150k. All other pins have no readings. Following the traces I can see they lead to the fan.

Do you have needle or electric iron? If you have, please break where the short circuit is.

or, how about you send me a new board that's not defective?