How to replace the fuel meter assembly

If the fuel meter on your car has stopped measuring the fuel level, it is most likely broken. A broken fuel meter is not only annoying but can also be dangerous because you won't be able to tell when you're about to run out of gas.

The fuel meter works like a rheostat, which constantly measures the current at different levels. Some fuel meter assemblies are simply mounted with two screws inside the dashboard, while other fuel meter assemblies are part of a group on the instrument cluster. This panel is usually made of thin plastic with internal wiring soldered on, like a piece of paper with lines on it.

A rheostat is an electrical device that is used to control electric current by changing resistance. Inside the rheostat is a coil wound loosely at one end and tightly wound at the other. There are several ground connections throughout the coil, usually made from pieces of metal. On the other side of the coil is another piece of metal that is powered by a car battery when the key is turned on. The stem acts as a connector between positive and ground inside the base.

When fuel is poured into the fuel tank, the float moves as the fuel tank fills up. As the float moves, the rod attached to the float moves across the coil connecting another resistance circuit. If the float is lowered, the resistance circuit is low and the electric current moves quickly. If the float is raised, the resistance circuit is high and the electric current moves slowly.

The fuel gauge is designed to register the resistance of the fuel gauge sensor. The fuel gauge has a rheostat that receives current supplied from the rheostat in the fuel gauge sensor. This allows the counter to change depending on the amount of fuel registered in the fuel tank. If the resistance in the sensor is completely lowered, the fuel gauge will register "E" or empty. If the resistance in the sensor is fully increased, the fuel gauge will register "F" or full. Any other location in the sensor will differ from registering the correct amount of fuel on the fuel gauge.

Causes of a malfunctioning fuel gauge include:

• Fuel Meter Assembly Wear: Due to driving conditions, the fuel meter assembly wears out due to the rod sliding up and down inside the rheostat. This causes the rod to gain clearance, resulting in an increase in resistance. When this happens, the fuel meter assembly starts to register as overfilled when the fuel tank is full, and there seems to be 1/8 to 1/4 tank left when the fuel tank is empty.

• Applying reverse charge to circuits: This happens when the battery is connected backwards, i.e. the positive cable is on the negative terminal and the negative cable is on the positive terminal. Even if it only happens for a second, dashboard circuits can be damaged due to reversed polarity.

• Wiring Corrosion: Any corrosion of the wiring from the battery or computer to the gauge and fuel gauge will cause more resistance than normal.

If the fuel meter assembly fails, the engine management system will record this event. The fuel level sensor will tell the computer about the level and resistance being sent to the fuel meter. The computer will communicate with the fuel meter and determine the settings with its rheostat and sender rheostat. If the settings do not match, the computer will issue a code.

Fuel meter assembly fault codes:

• P0460
• P0461
• P0462
• P0463
• P0464
• P0656

Part 1 of 6. Check the condition of the fuel meter assembly.

Since the fuel level sensor is inside the dashboard, it is impossible to check it without disassembling the dashboard. You can check the fuel meter to see how much fuel is left relative to the actual amount of fuel in the fuel tank.

Step 1: Refuel the car. Refuel the car until the fuel pump at the gas station stops. Check the fuel meter to see the level.

Document the pointer position or percentage of fuel level.

Step 2: Check when the low fuel light comes on.. Drive the vehicle to the point where the low fuel indicator light comes on. Check the fuel meter to see the level.

Document the pointer position or percentage of fuel level.

The fuel gauge should come on when the fuel gauge reads E. If the light comes on before E, then either the fuel gauge sensor or the fuel gauge assembly has too much resistance.

Part 2 of 6. Preparing to Replace the Fuel Gauge Sensor

Having all the necessary tools and materials in place before starting work will allow you to get the job done more efficiently.

Necessary materials

• Hex key set
• socket wrenches
• Flash
• Flat head screwdriver
• needle nose pliers
• Ratchet with metric and standard sockets
• Torque bit set
• Wheel chocks

Step 1: Park your vehicle on a level, firm surface.. Make sure the transmission is in park (for automatic transmission) or 1st gear (for manual transmission).

Step 2: Attach the front wheels. Place wheel chocks around tires that will remain on the ground.

In this case, the wheel chocks will be located around the front wheels, since the rear of the car will be raised.

Apply the parking brake to block the rear wheels from moving.

Step 3: Install a nine volt battery in the cigarette lighter.. This will keep your computer running and save the current settings in the car.

• AttentionA: If you don't have a XNUMXV power saving device, you can skip this step.

Step 4: Disconnect the battery. Open the car hood to disconnect the battery.

Remove the ground cable from the negative battery terminal to disconnect power to the fuel pump.

• AttentionA: It is important to protect your hands. Be sure to wear protective gloves before removing any battery terminals.

• Functions: It is best to follow the vehicle owner's manual to properly disconnect the battery cable.

Part 3 of 6. Remove the fuel meter assembly.

Step 1: Open the driver side door. Remove the instrument panel cover using a screwdriver, torque wrench, or hex wrench.

• Attention: On some vehicles, it may be necessary to remove the center console before removing the dashboard.

Step 2: Remove the bottom panel. Remove the lower panel under the dashboard, if present.

This allows access to the instrument cluster wiring.

Step 3: Remove the transparent screen from the dashboard.. Remove the mounting hardware that secures the instrument cluster to the dashboard.

Step 4: Disconnect harnesses. Disconnect harnesses from instrument cluster. You may need to reach under the panel to remove the straps.

Label each harness with what it connects to on the instrument cluster.

• AttentionA: If you have a car up to computer systems and have a conventional fuel meter that is mounted on the dash, you will need to remove the mounting hardware and remove the meter from the dash. You may also need to remove the light from the meter.

Step 5: Remove Meter Mounting Hardware. If your meter can be removed from the instrument cluster, do so by removing the mounting hardware or retaining tabs.

• AttentionA: If your dashboard is one piece, you will need to purchase a whole dashboard to secure the fuel meter assembly.

Part 4 of 6. Installing the new fuel meter assembly.

Step 1: Install the fuel meter assembly into the dashboard.. Attach the hardware to the fuel meter to secure it in place.

• AttentionA: If you have a car with pre-computer systems and you have a conventional fuel meter that is mounted on the dash, you will need to mount the meter on the dash and install the mounting hardware. You may also need to set the light to a meter.

Step 2. Connect the wiring harness to the instrument cluster.. Make sure each harness connects to the cluster at the points where it was removed.

Step 3: Install the instrument cluster into the dashboard.. Secure all connectors in place or screw on all fasteners.

Step 4: Install the Clear Shield into the Dashboard. Tighten all fasteners to secure the screen.

Step 5: Install the bottom panel. Install the bottom panel to the dashboard and tighten the screws. Install the dashboard cover and secure it with the mounting hardware.

• AttentionA: If you had to remove the center console, you would need to reinstall the center console after installing the dashboard.

Part 5 of 6. Connect the battery

Step 1 Connect the battery. Open the car hood. Reconnect the ground cable to the negative battery post.

Remove the nine volt fuse from the cigarette lighter.

Tighten the battery clamp to ensure a good connection.

• AttentionA: If you have not used a nine volt battery saver, you will need to reset all settings in your vehicle such as the radio, power seats, and power mirrors.

Step 2: Remove the wheel chocks. Remove the wheel chocks from the rear wheels and set them aside.

Part 6 of 6: Test drive the car

Step 1: Drive the car around the block. During the test, overcome various bumps so that the fuel splashes inside the fuel tank.

Step 2: Check for warning lights on the dashboard.. Watch the fuel level on the dashboard and check for the engine light to come on.

If the engine light comes on after replacing the fuel meter assembly, additional diagnostics of the fuel electrical system may be required. This issue may be related to a possible electrical problem in the vehicle.

If the problem persists, contact a certified specialist, for example, from AvtoTachki, to inspect the fuel gauge sensor and diagnose the problem.