P204E Fault Code

Reductant Pressure Sensor Circuit Intermittent/Erratic

• What does that mean?
• Symptoms
• Causes
• Solutions

The P204E fault code relates to the Reductant Pressure Sensor Circuit, indicating that there is an intermittent or erratic signal present. This can affect the performance of the selective catalytic reduction (SCR) system, which is critical for reducing harmful emissions in diesel engines. The issue can cause miscommunication between the sensor and the engine control module (ECM), leading to inefficient SCR operation.

What are the symptoms of the P204E code?

Common symptoms associated with a P204E error code include:

• Check Engine Light activated on the dashboard
• Decreased engine performance and fuel efficiency
• Increased exhaust emissions
• Possible inability to start the engine due to SCR system malfunctions
• Warning messages related to the SCR system

What causes the P204E code?

The primary causes of a P204E fault code may include:

• Faulty reductant pressure sensor
• Wiring issues such as frayed or shorted wires
• Poor connections within the sensor circuit
• Defective ECM or software issues
• Contamination or buildup in the reductant system

How to fix P204E?

To resolve a P204E fault code, it is recommended to:

• Inspect the reductant pressure sensor for damage and replace it if faulty.
• Check the wiring and connectors for any signs of wear, corrosion, or loose connections.
• Clear the fault codes and test drive the vehicle to see if the code reappears.
• If issues persist, consider ECM diagnostics for software updates or faults.
• Consult a professional mechanic if the problem is complex or ongoing.