With a diagnostic computer (OBD reader), one can read fault codes and live data. In the event of a fault, it may be necessary to perform a measurement. With a multimeter or oscilloscope, electrical components and systems in a vehicle can be measured. In case of faults, the measurement results can provide clarity on defective components or wiring. To perform measurements, one must be able to track the correct wire. Therefore, it is often necessary to consult a wiring diagram. The diagram shows, among other things, wire colors and thicknesses between a control unit, a sensor, or an actuator. If a breakout box is available, it can save time because the measurement connections are easily accessible.
