This code indicates that the primary engine or body computer is no longer receiving digital data signals from the fuel level sensor. It typically points to a failure in the local communication network, such as a LIN bus or CAN bus, rather than a simple analog voltage issue. As a result, the vehicle cannot accurately read or display the amount of fuel in the tank.
The internal electronics of the fuel level sender inside the fuel tank have failed, preventing it from transmitting data over the network.
An open circuit, short to ground, or corrosion in the wiring harness between the sensor and the controlling module disrupts the communication signal.
A localized failure on the communication bus, such as a LIN or CAN circuit, isolates the fuel level sensor from the rest of the network.
The module that directly communicates with the fuel level sensor has an internal circuit failure preventing it from receiving the signal.
The main engine computer has failed internally, which is highly unlikely and should only be considered after all other possibilities are eliminated.
Yes, drivability is usually unaffected, but you will not know how much fuel is in the tank, which could lead to running out of gas unexpectedly.
Not necessarily. The fuel level sensor is often physically attached to the fuel pump assembly, but a communication failure usually means the sensor's electronics or wiring have failed, not the pump motor itself.
Almost never. Mechanics commonly warn against replacing the PCM for a U0676 code because the failure is almost always located at the fuel level sensor, the wiring, or the network bus. The PCM is rarely the cause.
It depends on the cause. Fixing a wiring issue under the vehicle might be simple, but replacing the fuel level sensor often requires dropping the fuel tank or removing the fuel pump assembly, which can be complex.