A wiring harness testing assembly for testing a wiring harness for wiring faults includes a puck that is positionable on a female coupler of a wiring harness on a semi-truck and the puck is foraminous. A plurality of testing lights is provided and each of the testing lights has a contact that is insertable through a respective foramen in the puck to electrically engage the female coupler of the wiring harness when the puck is positioned on the female coupler. Furthermore, respective ones of the testing lights are turned on when the contact on the respective testing light completes a circuit with a respective wire on the wiring harness thereby facilitating the respective wire to be tested for continuity.