The first LED on the board is the “reverse polarity” warning. If this light is coming on, you will need to switch the red and black wires.
On the KidWind Power Output Board (KW-POBD), there is a “Visual Voltmeter” series of LEDs that progress from green to yellow to red to indicate the voltage. There is also a red LED at the upper-left labeled “Reverse Polarity”, which is a warning light that the board is connected to read a negative voltage instead of a positive voltage. If you reverse the polarity (change the positions of the red and black wires), it should fix the issue.
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