Description:

This diagnostic trouble code is set when the DEF dosing unit pressure is detected to be moderately high. Elevated pressure levels can indicate a potential blockage or malfunction within the DEF system that may affect proper DEF dosing.

Reaction:

The ECU may adjust the operation of the DEF system to manage the elevated pressure, potentially impacting DEF injection and overall emissions control efficiency.

Recommendations:

• Inspect DEF Dosing Unit and Lines: Check for blockages or restrictions in the DEF dosing unit and associated lines. Clean or replace components as necessary.
• Verify Pressure Relief Mechanism: Ensure that the pressure relief valves or mechanisms are functioning correctly.
• Check for Contaminants: Inspect the DEF for any contaminants that could cause pressure issues and clean the system if necessary.
• Test Pressure Sensors: Verify that the pressure sensors are providing accurate readings and replace any faulty sensors.
• Reset ECU and Monitor System: After addressing the pressure issue, reset the ECU to clear the fault code and monitor the system to ensure normal operation.

Note:

Maintaining the correct pressure in the DEF dosing unit is essential for effective DEF injection and proper functioning of the aftertreatment system. Regular maintenance can help prevent pressure-related issues.