First, you can obtain pin information by consulting the technical manual of the induction cooker or the specification of the CPU.
Secondly, a multimeter or oscilloscope can be used to test the voltage, current or signal waveform of the pin to determine its function.
In addition, its possible function can be inferred by observing the circuit layout and connection mode around the pin.
Finally, you can use online resources, such as technical forums or communities, to seek help and advice from other induction cooker maintenance personnel or electronic engineers.
From the copper foil area, it can be judged that the three leading feet of the main board FAN, the largest copper foil area is the ground wire, the middle is the power supply 12V, and the left is the fan speed and working status detection. The best way to do this is to test it with a multimeter