P203E Fault Code

Reductant Level Sensor Circuit Intermittent/Erratic

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

The P203E fault code indicates an issue with the reductant level sensor circuit, which is responsible for monitoring the level of diesel exhaust fluid (DEF) in your vehicle's tank. When the sensor circuit is intermittent or erratic, it can lead to inaccurate readings and affect the overall performance of the emissions system.

• The reductant level sensor plays a critical role in SCR (Selective Catalytic Reduction) systems.
• An intermittent signal may cause the vehicle's engine control unit (ECU) to trigger the Check Engine Light (CEL).
• Proper levels of DEF are essential for reducing nitrogen oxides (NOx) emissions and ensuring compliance with environmental regulations.

What are the symptoms of the P203E code?

When encountering a P203E code, several symptoms may become apparent:

• The Check Engine Light (CEL) may illuminate on the dashboard.
• You may notice a lack of engine power or performance issues.
• Emissions-related warnings may trigger due to the faulty sensor.
• In some cases, the vehicle may enter limp mode to reduce emissions until the fault is resolved.

What causes the P203E code?

The erratic behavior of the reductant level sensor circuit can be attributed to various factors, including:

• Corrosion or poor connections in the wiring and connectors.
• A malfunctioning or damaged reductant level sensor.
• Issues with the engine control module (ECM) or software glitches.
• Low or contaminated diesel exhaust fluid affecting sensor performance.

How to fix P203E?

To address the P203E fault code, the following steps should be taken:

• Inspect the wiring and connections of the reductant level sensor for signs of damage or corrosion.
• Test the reductant level sensor's functionality and replace it if faulty.
• Check the quality of the diesel exhaust fluid; if it's contaminated, it may need to be replaced.
• Update or reprogram the engine control module (ECM) if necessary.