Method and systems for testing an electrical circuit

A system for monitoring an electrical system of a vehicle, comprising:

• an electrical panel including a first connector coupled to a plurality of panel wires;
• a wiring harness including a plurality of harness wires coupled to a second connector adapted to couple to the first connector, where each harness wire of the plurality of harness wires corresponds to one panel wire of the plurality of panel wires;
• and
• a testing apparatus including a third connector coupled to the first connector, a fourth connector coupled to the second connector, and a fifth connector including a plurality of testing ports, each port of the plurality of testing ports coupled to a testing wire spliced from a corresponding main wire of a plurality of main wires of the testing apparatus coupling the third connector to the fourth connector, where each main wire corresponds to a corresponding panel wire and harness wire, and where the third connector and second connector are directly mounted to a housing of the testing apparatus and the first connector is tethered to the housing via the plurality of main wires.