[b][user=20667]Mack[/user] wrote: [/b][quote]I am still confused as to how his rig could differentiate between High and Low level lights when all the stop lights on the caravan are powered from Pin 6 on the socket.
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I can see how it might detect that a light had failed, even though there were two others on the same circuit. Volvos have had devices that warn the driver if a brake light has failed for over 30 years – it just measures the lower current drawn by one fewer lamps.
Presumably this tester is a more sophisticated version. The Volvo one can be confused by mismatch between bulbs of different manufacture, or I have found by a bulb that is approaching failure.
But like you I cannot see how it can distinguish left from right,or centre.
