Embodiments of the present disclosure are directed to a universal junction box for solar modules that comprises multiple sub-assemblies with a replaceable diode black and an open-IP plug sub-assembly. The universal junction box includes a first sub-assembly (junction box platform), a second sub-assembly (a replaceable diode block), and a third sub-assembly (an open sub-assembly or plug sub-assembly. If the electronics in the diode block becomes defective, a new replaceable diode block can be used to substitute into the defective diode black without having to replace the entire junction box. The open-IP plug sub-assembly provides the flexibility to couple a variety of cable sub-assembly or IMEs to the universal junction box as long as a particular selected cable sub-assembly fits with the dimension of the open-IP plug sub-assembly.