ISO 3732 is an international standard that specifies the requirements for 7-pin connectors of type 12 S. These connectors are used for the electrical connection between towing vehicles and trailers with a nominal voltage of 12 volts. The standard defines the dimensions, the assignment of the contacts (pins), and the technical requirements for these plugs and sockets. By following these specifications, the interchangeability and reliability of the electrical connections are ensured.

Important points of ISO 3732:

  • Standard: ISO 3732
  • Voltage: 12 volts
  • Usage: For additional lighting systems such as reversing lights and fog lights.
  • Purpose: Ensures a standardized and reliable electrical connection between the towing vehicle and the trailer for additional functions.

Pin configuration and functions:

  1. Reversing lights (yellow): Controls the operation of the trailer's reversing lights.
  2. (n/a): No specific assignment.
  3. Ground (white): Serves as the common ground connection.
  4. Power supply (green): Provides power for additional equipment such as refrigerators.
  5. (n/a): No specific assignment.
  6. Switched power supply (red): Provides the power supply switched by the vehicle's ignition.
  7. Ground for pin 6 (black): Ground connection for the switched power supply.

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