The car microphone wiring harness is a crucial component of the in-car hands-free system, responsible for transmitting audio signals, power, and grounding connections, ensuring clear communication.

The physical connections of the wiring harness usually involve multi-pin interfaces. For example, in a 28-pin interface, specific pins correspond to the functions of the microphone. Pin 4 is connected to the red signal line (positive terminal of the microphone signal), pin 5 is connected to the white wire (possibly a backup or differential signal line), pin 6 is connected to the yellow wire (possibly used for power or ground), and pin 19 is connected to the black wire (usually ground). The actual definitions need to be confirmed through measurement with a multimeter, as there may be significant differences among different vehicle models.