A wiring diagram is a visual representation of an electrical circuit. It displays the components of a circuit as simplified shapes. It also illustrates the power and signal connections between the devices.
Wiring diagrams often give information about the relative position and arrangement of devices and terminals, in order to help in the construction of the device.
Wiring diagrams are used for troubleshooting.
They also help the technician to make sure all the connections were made in the correct location and that all equipment is present.