This International Standard specifies the dimensions of, and requirements for, 7-pole connectors of type 12 S and their contact allocation for the electrical connection of towing (passenger cars or light commercial vehicles) and towed vehicles with 12 V nominal supply voltage, thus ensuring interchangeability. A 12 S connector is intended to be used in addition to a 12 N connector according to ISO 1724 where more than 7 poles are required.
NOTE For new developments and where more than 7 poles are required, as an alternative to the use of the 7-pole connector according to this International Standard and ISO 1724, the use of 13-pole connector in accordance with ISO 11446 [1] may be required.