A protection diode is used in a circuit so that current will not flow in the reverse direction in the circuit. The diode is a cylindrical semiconductor with two wires that extend from the sides located behind the doorbell inside the housing. How To Wire A Trailer If Your Car Has Separate Signal And What Wire Do I Tap Into Ranger Forums The Ultimate Ford Me09 Use the soldering iron to melt a small drop of solder to the twisted wire joint created between the diode and the first wire. How to wire a diode . Connect the diode in the opposite direction and it will block the current. Solar panels with more charge current than this would require a larger diode such as our 85 amp diode. How to wire diodes a diode acts like a one way valve for electricity. Connect the diode in one direction and current will flow through the diode. A diode has two connec...