Remove the first aid kit compartment. Remove the fuel sender. Carefully remove the outer cover on the sender by removing the small nut on the bottom. Ck to see if the wires are intact that the float slides on. Ck the contacts on the bottom as they are the ones that turn on the light. Ck the small holes on the outer cover of the sender. they can clog and not let the fuel flow into the sender. The contacts at the bottom are prone to deterioration from junk and water in the fuel. If not fixable, then you will have to replace the unit. Good luck

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My Truck.. 2007 DODGE, 5.9 Cummins, 6spd stick, 4X4. My car..1977 240D, OTHER WHEELS...1955 VW Oval window bug, European Delivery (Holland) with a 1700cc, 2 barrel, Porsche drum brakes. 1939 WILLYS Pick-up. 1967 Triumph 200cc Tiger Cub. 1976 Honda 550F 4cyl Motor Cycle.