Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the sensor that checks for water in the fuel. It's like a warning light telling you that the sensor isn't working right.
The P238C code is triggered when the Engine Control Module (ECM) detects a low voltage signal from the water in fuel sensor B circuit.
The water in fuel sensor is designed to detect the presence of water in the fuel system. When the sensor B circuit sends a low voltage signal to the ECM, it indicates a potential issue with the sensor or its circuit, such as a short circuit or a faulty sensor.
• Check Engine Light illuminated
• Possible poor engine performance
• Fuel contamination warning
• Faulty water in fuel sensor
• Damaged or corroded wiring or connectors
• Short circuit in the sensor circuit
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the water in fuel sensor for proper operation.
• Replace the faulty water in fuel sensor.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly check and replace fuel filters.
• Use high-quality fuel to prevent contamination.
• Perform regular maintenance checks on the fuel system.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regularly maintain the fuel system to prevent issues.
Check with the vehicle manufacturer for specific warranty coverage on sensors.
This code has been associated with vehicles that have had issues with fuel contamination due to poor fuel quality.
Moderate – While the vehicle may still operate, it is important to address the issue to prevent potential engine damage.
Ignoring this code may lead to engine performance issues and potential safety hazards. Always ensure your vehicle is in good working condition.
• Engine running
• Fuel system under normal operating conditions
The water in fuel sensor is typically located near the fuel filter or within the fuel tank.
Q: What does a water in fuel sensor do?
A: It detects the presence of water in the fuel system to prevent engine damage.
Q: Can I drive with a P238C code?
A: While you may be able to drive, it's recommended to address the issue promptly to avoid potential engine problems.
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