Just plug the tester in the 7 pin socket or the 7 pin plug of the trailer or caravan and press the yellow button on the side of the tester. This 12V 7 Pin Trailer Lights Plug & Socket Wiring Circuit Tester is designed for testing the lighting circuits on both towing vehicles and trailers/caravans etc.
eBay
This tester has one side to connect the 7-pins plug of a trailer and another side to connect the 7-pins socket of a car. This tester indicates quickly if a failure concerns the wiring of the car or the wiring of the trailer.
eBay
Automotive7Pin to 13Pin Towing Trailer Tow Bar Caravan Light Wiring Circuit Tester Plug Socket UK. This tester is for a trailer/caravan and tow bar socket/plug checker. -Just plug the tester in the 7 pin socket or the 7 pin plug of the trailer or caravan and press the yellow button on the side of the tester.
eBay
This tester has one side to connect the 7-pins plug of a trailer and another side to connect the 7-pins socket of a car. This tester indicates quickly if a failure concerns the wiring of the car or the wiring of the trailer.
eBay
Trailer tester 12 VOLT hand tester Lighting and cable tester for trailers/caravans and towing vehicles for 7-pin and 13-pin PLUGS and SOCKETS using the adapter supplied. Simply plug the lighting and cable tester into the socket or plug to be tested, press the test button and a clear diagnosis is made via the LED display.
eBay
CAN BE MADE FOR USE WITH DEWALT MAKITA 18V BATTERIES OR MILWAUKEE M12 OR M18 BATTERIES. Manual switch trailer lighting test box for use with 18v dewalt battery, built in 12v regulator. Full 13 pin functionality to test all lights and 12v permanent and switched functions of trailer.
eBay
Tester has one side to connect the 7-pins plug of a trailer and another side to connect the 7-pins socket of a car. This tester indicates. tester Yellow No. 1 indicator will light up if the LED is not lit, the.
eBay
This tester has one side to connect the 7-pins plug of a trailer and another side to connect the 7-pins socket of a car. This tester indicates quickly if a failure concerns the wiring of the car or the wiring of the trailer.
eBay