amateurw7vp

In working on the instrument cluster for the '85 diesel RV conversion the cluster itself uses "C" connector pin 4 for ground and 5 for the "FU" or fuel sensor. Both wires run to the fuel sensor itself. The actual "C" connector has a pink wire at pin 4 and the ground is on pin 5 and the "FU" is on pin 6. The cluster does not match these pins and pin 6 is not connected in the cluster itself. Does anyone know what the pink wire is? I can't find it on any of the schematics I have. (I moved the W/B wire to pin 4 and the Y/R wire to pin 5 on the connector to match the cluster).