P203F Fault Code

Reductant Level Low

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

The P203F fault code indicates a low reductant level in the vehicle's emissions control system. This typically refers to the diesel exhaust fluid (DEF) that is used in selective catalytic reduction (SCR) systems to reduce nitrogen oxides (NOx) emissions. When the DEF level drops below a certain threshold, the engine control module (ECM) triggers this code to alert the driver.

What are the symptoms of the P203F code?

Common symptoms associated with the P203F code may include:

• Warning lights illuminated on the dashboard indicating low DEF.
• Decreased engine power or performance due to derate strategies in effect.
• Potential driveability issues as the vehicle attempts to comply with emissions regulations.

What causes the P203F code?

There are several potential causes for a low reductant level condition, including:

• Insufficient filling of the diesel exhaust fluid tank.
• Leaks in the DEF system leading to fluid loss.
• Defective level sensor that incorrectly reports fluid levels.
• Contamination of the DEF due to improper storage or handling.

How to fix P203F?

To resolve the P203F fault code, follow these steps:

1. Check the DEF tank level and replenish the fluid if it is low.
2. Inspect the DEF system for any leaks or damages, including hoses and connectors.
3. Verify the functionality of the DEF level sensor and replace it if faulty.
4. Clear the fault codes and test drive the vehicle to ensure the issue is resolved and that no further codes are triggered.