So let’s start measuring. First, let’s check the power connector.
Take two red and black jerk pins from the meter and connect the black jerk pin to the black wire on the P1 connector. You can sew on any black string you like. Insert the red jerk pin from the meter into the red wire from the P1 connector. Then the meter box will show + 5V in DCV. Then the power supply is at full power. If it shows 3V, the power output is not good. In the same way, other wires must also measure the output voltage. When measuring 5V wires, it must be 5V. When measuring 3.3V wires, the voltage should be 3.3V. To measure 12V wires, you need to change the channel of the meter to 50V.