Code Definition: P1253 - Fuel Level Sensor B Circuit High Input
The P1253 code is a generic trouble code that indicates a high input from the fuel level sensor circuit in bank B. The fuel level sensor is responsible for measuring the fuel level in the tank and sending a signal to the engine control module (ECM) so that the ECM can calculate the appropriate fuel injection volume. A high input from the fuel level sensor circuit can cause problems with the engine's performance and fuel efficiency.
Possible Causes:
- Faulty fuel level sensor
- Damaged or corroded wiring harness
- Loose or damaged electrical connectors
- Malfunctioning fuel pump or fuel delivery system
- Incorrect fuel level sensor calibration
- Overfilled fuel tank
Symptoms:
- Illuminated check engine light
- Inaccurate fuel level readings
- Engine stalling or hesitation
- Difficulty starting the engine
- Decreased fuel efficiency
Diagnostic Procedure:
- Use a scan tool to retrieve the trouble code and view the freeze frame data to determine when the code was set and under what operating conditions.
- Check the fuel level sensor and its connections for any signs of damage or wear.
- Inspect the wiring harness and connectors for any signs of damage or corrosion.
- Test the fuel pump and fuel delivery system to ensure they are functioning properly.
- Check the fuel level in the tank and make sure it is below the maximum level required by the fuel level sensor.
- Calibrate the fuel level sensor if necessary.
- If the problem persists, consider replacing the fuel level sensor or the affected component.
- Clear the code and perform a road test to verify the repair.
Repair Information:
- Replace the faulty fuel level sensor.
- Repair or replace any damaged or corroded wiring harness or connectors.
- Replace the malfunctioning fuel pump or fuel delivery system component.
- Reprogram the fuel level sensor calibration.
- Clear the code and perform a road test to verify the repair.
