Just plug the tester in the 7/13 pin socket or the 7/13 pin plug of the trailer or caravan and press the yellow button on the side of the tester. i2.1ca69AYS9AYSKR" style="box-sizing: border-box; -webkit-tap-highlight-color: transparent; outline: 0px; margin: 0px; padding: 0px; height: 24284.2px; position: absolute; top: 0px; visibility: hidden; width: 1195.33px; z-index: -1;">.
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