3. ANTILOCK SYSTEM - ELECTRICAL SYSTEM.

3.1 ‘Antilock Systems’ must be powered by a 12V electrical supply system, through a connection to the towing vehicle, using a connector conforming to DIN Standard 72570 configured for 12 volt operation.

3.2 The connector must be wired to have the following functions :

3.2.1 For trailers not equipped to tow another trailer:

Pin 1 +ve high current trailer solenoid valve supply

Pin 2 +ve low current trailer electronic unit supply

Pin 3 -ve low current trailer electronic unit supply

Pin 4 -ve high current trailer solenoid valve supply

Pin 5 trailer antilock failure, switched to -ve (eg pin 3 or pin 4) upon fault detection

3.2.2 For trailers equipped to tow another trailer:

Pin 1 +ve high current trailer solenoid valve supply, 30 amps minimum rated capacity

Pin 2 +ve low current trailer electronic unit supply, 4 amps minimum rated capacity

Pin 3 -ve low current trailer electronic unit supply, 6 amps minimum rated capacity

Pin 4 -ve high current trailer solenoid valve supply, 30 amps minimum rated capacity

Pin 5 trailer antilock failure, switched to -ve (eg pin 3 or pin 4) upon fault detection, 2 amps minimum rated capacity

3.3 Any break in the supply of electricity to an ‘Antilock System’ and any electrical failure of an ‘Antilock System’ other than a failure of one or all of the electrical conductors between pins 3, 4 and 5 on the electrical connector and the antilock control module must be signalled to the towing vehicle by connecting Pin 5 on the electrical connector to -ve (ie pin 3 or pin 4).

3.4 Each ‘Antilock System’ must connect pin 5 to -ve (eg pin 3 or pin 4) when initially energised and disconnect pin 5 from -ve after not less than 2 seconds or at the latest when the trailer reaches a speed of 15 km/h and no defect is present.