Description:

This diagnostic trouble code is triggered when the temperature sensor in the Diesel Exhaust Fluid (DEF) tank detects an issue with accurately measuring the fluid’s temperature. This problem can affect the DEF dosing system, which is critical for maintaining the correct emissions control through selective catalytic reduction.

Reaction:

The ECU may adjust DEF dosing rates or trigger a fault mode to prevent incorrect DEF injection, which could lead to inefficient catalytic conversion and potential emission standard violations.

Recommendations:

• Inspect DEF Temperature Sensor: Check the sensor for damage, corrosion, or connectivity issues that might affect its function.
• Test Sensor Functionality: Use diagnostic tools to verify the sensor’s output against known temperature values.
• Replace Faulty Sensor: If the sensor is found to be defective, replace it to restore accurate temperature measurement.
• Clear Fault Codes and Reset ECU: After replacement, clear any fault codes from the ECU and reset it to ensure the system recognizes the new sensor and recalibrates accordingly.
• Verify System Operation: Conduct a system check to ensure the DEF system functions correctly with the new sensor under various operating conditions.

Note:

Regular maintenance of the DEF system and its sensors is crucial for emission control. Faulty temperature readings can lead to improper DEF dosing, adversely affecting emission control and engine efficiency.