<div style="color:black;font: 10pt arial;">I have a 5 pin horn relay on my 1976 TR6 that appears to be original. I am only getting 9 volts on the purple/yellow output to the horns so I am assuming a bad relay, but I cannot find the purpose of the 5th pin. It is not the horn ground from the push button, input from the fuse box or output to the horns. My wiring diagrams all show only 4 pins for the relay. I cannot read the pin identifiers so there is no help there. The wire is black with a tracer color that is faded so I cannot determine what it is. Any ideas would be appreciated.