Fuel Gauge Sender: Testing and Inspection
IN VEHICLE TESTFuel Sender Connector:
1. Inspect the fuel tank for distortion or damage.
NOTE: If the fuel tank is distorted or damaged, it must be serviced or replaced before further testing.
2. Connect an ohmmeter to the ground terminal of the fuel sender connector, the other lead to the variable resistor terminal. If the resistance of the sensor is above 160 ohms or below 15 ohms, replace the fuel sender.
3. Fill the tank to capacity. The ohmmeter should read between 145 ohms and 160 ohms resistance. If the FULL tank sender reading is below 145 or above 160 ohms the sender should be replaced.
4. Drain all the fuel from the fuel tank observing the ohmmeter reading while the fuel tank is being drained. Resistance should increase smoothly without jumping or hesitating. If resistance reading jumps or hesitates, replace fuel sender unit.
5. When the fuel tank is empty, the ohmmeter reading should be between 15 ohms and 22 ohms resistance. If the EMPTY tank fuel sender resistance reading is below 15 ohms or above 22 ohms, replace sender unit.
BENCH TEST
1. Connect an ohmmeter to the ground terminal of the fuel sender connector and the other lead to the variable resistor terminal. When the float rod is against the EMPTY stop the sender reading should be 14 - 18 ohms. If the resistance reading is below 14 ohms or above 18 ohms, the fuel sender must be replaced.
2. Watch the ohmmeter reading while slowly moving the float between the empty and full float rod stops. The resistance should increase and decrease smoothly without jumping or hesitation. The ohmmeter should read between 14 ohms and 165 ohms. If resistance reading jumps or hesitates, replace the fuel sender.
3. Move the fuel rod to the FULL stop position. The ohmmeter should read between 155 ohms and 165 ohms. If the ohmmeter reading is below 155 ohms or above 165 ohms, replace the fuel sender.
4. Before installing a fuel sender unit, the wire harness connector should be connected to the fuel sender unit and the float moved from the EMPTY to FULL stops to check the fuel gauge readings.