What does it mean when a fuel gauge stops working? Most drivers encounter one of three scenarios:
- The gauge shows an empty tank even when you add fuel.
- The gauge shows a full tank no matter how many miles you drive.
- The gauge swings wildly between full and empty. It never settles.
But is that a bad thing? Yes, because you won’t realize that you’ve run out of fuel until your vehicle comes to a stop. That sounds more like an inconvenience than a serious challenge. However, permitting the gas to run low attracts adverse side effects for your vehicle, including:
- You’re more likely to clog the filter.
- The fuel pump may overheat. The component will incur irreparable damage if you routinely run low on gas.
- The engine can misfire.
But why would a fuel gauge fail? To answer that question, you must first understand how these devices work:
- The fuel gauge is far more complex than the meter you see on your dashboard. It gets readings from a device known as a fuel-sending unit. Without that fuel-sending unit, the gauge is worthless.
- Strange as it might sound, a fuel-sending unit’s operations are comparable to the workings of a toilet. A toilet has an arm that floats in the reservoir. When you flush the toilet, the arm drops because of the water leaving the reservoir. This opens the valve and allows new water to enter. As the water level rises, so does the arm. Eventually, the arm gets to a point where it closes the valve, preventing more water from flowing into the tank.
- The fuel gauge has a similar arm that floats in the fuel tank. It will rise or fall with the fuel level. You can also trust this arm to communicate the fuel quantity to the gauge via a variable resistor.
- A metal rod connects the float arm to the variable resistor.
That sounds like a simplistic description of a fuel gauge’s work. However, most vehicles follow a similar principle, including the various Kia models. Therefore, if you have experience troubleshooting defective fuel gauges in other cars, you can do the same for a Kia.
The following tends to explain a Kia fuel gauge that won’t work.
- The fuel gauge is dead.
- The entire instrument cluster has a fault.
- The resistor has an open circuit.
- The float is no longer connected to the metal rod.
- The variable resistor is faulty.
- The system has damaged, disconnected, or corroded wires. Damaged wires cannot send information to the fuel gauge. And if they do, they may transmit incorrect data, tricking you into thinking that a full tank is empty or vice versa.
- If the gauge is fluctuating, the experts at Toyota-of-Orlando blame a stuck float. The car will occasionally jolt the arm from its place, hence the fluctuating readings.
Ultimately, you may require a mechanic’s assistance. They can determine whether or not the fuel-sending unit as a whole is dead. But before coming to that conclusion, they will search for circuit problems.
A loose connection or corroded wire can wreak havoc on your Kia. An expert can analyze the vehicle’s electrical system to find the fault.
Troubleshooting A Kia Fuel Gauge That Doesn’t Work
You can’t fix Kia’s fuel gauge unless you find the source of its problems. That means applying the following troubleshooting steps:
1). Does the fuel gauge have sufficient power?
You can find out by testing the component with a multimeter:
- Turn the key in the ignition to the on position.
- Get a multimeter and test the voltage between the ground and positive terminals. You will find them on the back of the gauge.
- You’re trying to determine whether the gauge gets 12 volts. Zero voltage points to a defective ignition circuit. The fuel gauge is fine. What if the multimeter shows 12 volts? This compels you to take a closer look at the fuel gauge and sender.
2). Test Sending Wire
You can eliminate the fuel gauge as a potential culprit once and for all by locating the sending wire. Check the back of the gauge. You’re looking for an ‘S’ label. What happens when you disconnect the wire? You will observe one of two outcomes:
- The gauge will jump to the highest reading. This is good because it shows that your fuel gauge is okay. You should look elsewhere.
- The gauge won’t jump to the highest reading. This points to a faulty fuel gauge. Get a new one.
What if the wire itself is at fault? You can confirm this suspicion by disconnecting the wire and testing its resistance with a multimeter. Zero Ohms hint at a bad sender.
4). Inspect The Sending Unit
Don’t tamper with the sending unit without checking the wiring. Find the harness that meets the fuel pump and sending unit’s electrical requirements. A visual inspection should reveal damage and corrosion.
If you’ve ruled out the wiring, inspect the sending unit. You’re looking for a broken float arm. If it seems okay, test the unit’s resistance. Connect a multimeter and move the float arm up and down. The manual will tell you the readings to expect.
Although, your initial focus here is to determine whether or not the multimeter detects resistance. You need a new sending unit if the resistance doesn’t change even when you move the float arm.
The old one is dead. This test doesn’t work with newer vehicles that position the fuel pump and sending unit within the same assembly. In such cases, perform a visual inspection. If you can see apparent signs of damage, such as disconnected wires and corroded float arms, take the Kia to a dealership.
That assumes you have a warranty. The dealership can connect a diagnostic scanner to the vehicle. They will make a recommendation based on the error codes they record. Otherwise, your best bet is to hire a mechanic.
Even if you own a diagnostic scanner, you need a mechanic to interpret the error codes and apply the relevant solutions. The last thing you want is to spend $800 on a new instrument cluster when the fault lies with a broken sending wire.
5). Self-Test Instrument Cluster
Every car has a self-test procedure for the instrument cluster. Check the manual to find yours. If you succeed, the needle will do a full sweep through the gauge, compelling you to look for the fault elsewhere.
If the needle fails to respond accordingly, the fuel gauge is the problem. You can either repair or replace it.
6). Replace The Blown Fuse
The fuse is the simplest problem to solve. The manual will show you the location of the fuse box. It will also show you the instrument cluster’s fuse.
If the instrument cluster’s fuse blows, replace it. You don’t fix fuses. You can perform the self-test again after installing a new fuse.