Lost Communication With Fuel Level Sensor C
What it means
A module expected regular network messages from the fuel level sensor, which reports how much fuel is in the tank and has stopped receiving them. This is a communication fault: the part may still be working, but its reports are not reaching the other modules. The most common real-world cause is a power, ground or connector problem at the module that went quiet.
Can I keep driving? Yes, but the gauge may be wrong, so track fuel by mileage and get it read.
What this part does
The fuel level sensor sits in the fuel tank, usually as a float on an arm, and measures how much fuel is left. The computer sends the reading to the fuel gauge and low fuel warning, and the engine computer also uses it for emissions tests. When it fails, the gauge may read wrongly, jump around, or stick.
Common symptoms
What you'll notice
- Fuel gauge stuck, erratic or reading empty
- Low-fuel warning shown wrongly
- Check-engine light on
- Fuel range reading missing
Common causes
Most likely first
- Damaged, loose or corroded connector or wiring at Fuel Level Sensor C
- Loss of power or ground (blown fuse, bad ground) at that module
- Network wiring fault or poor termination affecting several modules
- Failed sensor or module that is no longer sending messages
- Receiving module (usually the engine computer) fault
How to diagnose & fix
Work through it in order
- Read codes from all modules, not just the engine; several lost-communication codes together point to the network or power.
- Check fuses, power and ground at Fuel Level Sensor C and its control unit.
- Inspect its connector and wiring for corrosion, heat damage or chafing.
- Check the network wiring and connectors shared with other modules.
- Replace the part only if power, ground and network check out.
Related codes
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