This is Sinaptec 3d printer controller board i have build while ago. It runs on Arduino Nano V3 with Teacup Firmware and i have on major issue which i cannot solve by myself. Controller cannot heat up hotend, after sending gcode. PC shutdown (i suspect it takes too much 5V current from USB )
So far works: pc connection, motors, thermistors, endstops
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streamable.com]
What worries me the most is the second pic. those two LEDs on right should not be lit/glow
Tested MOSFETs with multimeter in diode test mode and there is no connection between drain and source.
Voltage regulator on left side takes 12.6V DC and output is stable 4.98V DC
And i am out of ideas how to solve this, especially when my know-how in electronics is basic at most. Any help or input will be appreciated.