What is this component on the BTT Octopus v1.1?

It's associated with CNC_FAN1 and I think it's not working.

My extruder cooling fan shorted and fried this little guy... I think it's a mosfet. The one next to it might not be working as well because my doomas decided to plug the fan into that one to test to make sure it is the fan that's dead, because it's a bit of a pain to change that fan. Anywho....

What happened was that the wires attached to the fan directly under the sticker had the isolation pulled back on each side. After installing it a while back, the wire became dislodged from the little wire keeper tab thingies and the exposed conductors twisted together and that was that.

Anyways... let me know if anyone knows what the component is. I have an extra BTT Octopus with bltouch port that never worked. After triple checking that, I'll just use it for parts if in fact the bltouch port doesnt work.

Thanks.

Edited 1 time(s). Last edit at 04/02/2022 01:27AM by CVRIV.

According to the circuit diagram [github.com]

The mosfet is a ES3400

Wow. I didn't know there was a diagram online for these. I found the pin-out diagram. Thanks a ton.

So I found something weird with my BTT Octopus v1.1 board. The board with the blown mosfet has a 10 Ohm resistor between the mosfet's gate and the IC fan buffer. IT's like this for all the fans on that board. It's suppose to be 10K Ohm according to the schematic. I checked another board and it has all 10K Ohm resistors from the IC buffer and all the gates.

What's going on here? So again, the fan wires solder to the fan behind the sticker got twisted the the conductive wires touched because the isolated sheath was receded. Maybe because whoever soldered the wires used to much heat for too long? I dont know.

I removed two mosfet 3400 from my defective board and soldered them to the board with the blown mosfets. when I powered it all up those fan ports, fan0 and fan 1 still didnt work, but the other fans did work. I desoldered the mosfets again and tested them. They work fine.

I started checking the resistors and noticed the values were different across them across the different fan ports. Before rtying to figure that out thats when I noticed the 100 resistors that are suppose to be 103 resistors.

Anyone have 100 resistors there?