2003 Dodge Ram 3500, Cummins HO
Installed auxillary fuel tank in bed, cut blue wire w/white tracer and ran wiring to electric switch valve harness. Gauge is not working with either tank (gauge is pegged at full). Rewired as original, gauge still not working. Have 9.5 volts at gauge end of wire, 3.2 ohms at sending unit end of wire. What should I check next???????????????