Fuel Gauge Indicates Full Or Greater At All Times (Single Tank - Except 4.3L)

Disconnect instrument cluster connector. Connect fused jumper wire between instrument cluster connector terminal No. 22 (Pink wire) and voltage. See Figure . Install another fused jumper wire between instrument cluster connector terminal No. 16 (Purple wire) and ground. Install fused jumper wire between instrument cluster connector terminal No. 31 (Black wire) and ground. Turn ignition on. If fuel gauge indicates full, replace instrument cluster connector. If fuel gauge indicates empty, go to next step.
Remove fused jumper wires from instrument cluster connector and reconnect connector. Disconnect fuel pump and sender (gasoline) or fuel gauge sender (diesel) connector. Connect a fused jumper wire between fuel sender connector terminal "B" (Purple wire) and ground. If fuel gauge indicates full, locate and repair open circuit in Purple wire between instrument cluster connector and fuel gauge sender. If fuel gauge indicates empty, go to next step.
If vehicle is gasoline powered, replace fuel pump and sender. If vehicle is diesel powered, install a fused jumper wire between fuel gauge sender connector terminals "A" (Black/White wire) and "B" (Purple wire). If fuel gauge indicates full, repair open circuit in Black/White wire between fuel sender and ground. If fuel gauge indicates empty, replace fuel gauge sender.