Faults of fuel level sensor
- mechanical damage;
- incorrect display of fuel level in the tank;
- wiring faults,
- contact oxidation;
- wear of the fuel gauge wiper;
- wear of contact tracks.
Symptoms of fuel level sensor faults
- fuel level indicator needle is at zero;
- sharp ascent and descent of the indicator needle while driving;
- the needle indicates an incorrect value with a full tank.
Causes of the fuel level sensor faults
- short circuit or disconnection of the contacts on the dashboard;
- pointer jamming on the dashboard;
- deformation of adjustment tabs;
- wedge of measuring float;
- lost contact of the sensor with the earth.
Diagnostics
First check the structural condition of the sensor. Very often its unprotected contacts are damaged due to moisture and dirt impact, and subsequent oxidation.
In addition, check the sensor resistance with an ohmmeter. It is worth noting that the fuel tank filling level affects the readings, so it is better to take them in an empty or full tank. The sensor resistance in the absence of fuel should be 230-330 ohms. When the fuel tank is full, a mark must be of 6-7 ohms.
If the indicator on the instrument panel does not respond at all, it is necessary to remove the cover and check the wiring.
The sensor is checked at a planned diagnosis of the fuel system, which is necessary to carry out once a year, or after 60 000-80 000 kms.
Repair and replacement of the fuel level sensor
If contact damage or corrosion occurs you can simply clean them. When disconnecting the sensor be careful not to damage the contact tabs. Otherwise, you will need a new sensor.
In case of incorrect readings the pointer itself can be adjusted. To do this, change the position of the float wiper to maximum, adjust the corresponding value to the indicator pointer and clip it.
Replacing the sensor is required when it is damaged or changed its level of resistance. After replacement it is necessary to calibrate for more accurately display of the fuel level.
Fuel tank sender unit finder for