4 Tips for Troubleshooting a Faulty Truck Fuel Gauge

truck fuel gauge

The readings on a truck fuel gauge are essential for understanding many aspects of driving. You need it to work to be sure you don’t run out of gas in the middle of nowhere and to judge what kind of mileage you get in your truck. If you have a problem with your fuel gauge, you need to be able to troubleshoot it quickly. Very often, the problem is a fairly simple one that can be easily resolved without professional repair.

Read on for some common problems and solutions that could help fix your truck.

1. Temperature Gauge

If the temperature and the fuel gauge aren't working, the first thing to check are the fuses. If the fuse for the fuel gauge have stopped working, your fuel gauge could be erratic and performing strangely. To fix the problem, you only need to fit a new fuse. After that, the fuel gauge should work without a problem.

If the fuse is fine, you will need to look at the voltage limiter. The location of this component in your truck will vary depending on the make and model, so check your truck’s service manual first. The chances are that the voltage limiter will be at fault, and by fixing it, the problem with both gauges will be resolved.

2. Corroded Wiring

One common reason for a fuel gauge not working in a truck is that the wiring has become corroded. There’s no quick way to check this, and you’ll need to trace the wiring using the appropriate diagram for your vehicle. You should be able to find this in the service manual. Trace wiring all the way from the fuel tank via the fuel pump to the fuel gauge on the dashboard. You can try putting Vaseline on all the connections if you’re not sure how good they are.

3. Sending Unit

The problem could also be in the sending unit. In order to test this, you’ll need to use a multimeter. Start by testing the fuel gauge to see if the resistance is normal. Go ahead and fill the tank completely rather than trying to guess the level. It will give you a benchmark to work from. When you’ve done this, take a multimeter and set it to the 0 to 100 Ohms range.

To carry out the test, put the meter’s red probe on the center post of the sending unit and the black probe to each of the other posts and check the reading. With a full tank, it should read between 9 and 10 Ohms. However, if you get a reading of between 96 to 98 Ohms, you will know the sending unit has a problem and will need to be replaced; the 96 to 98 Ohms reading is that of an empty fuel tank.

4. Bad Gauge

It’s possible that the fuel gauge itself has become faulty. The only way you’ll know for sure is when you’ve eliminated the other possibilities. When this happens, you’ll need to replace the entire fuel gauge. If you feel comfortable with this task, go ahead and carry out the repair. Otherwise, take it to a garage in the knowledge that you have saved on the expense of having them track down the problem for you.