P205B Fault Code

Reductant Tank Temperature Sensor Circuit Range/Performance

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

The P205B fault code indicates a problem with the reductant tank temperature sensor circuit, which may be experiencing issues related to its range or performance. This sensor is crucial for monitoring the temperature of the diesel exhaust fluid (DEF), ensuring optimal operation of the selective catalytic reduction (SCR) system that helps reduce harmful emissions.

What are the symptoms of the P205B code?

Symptoms of a P205B code may include:

• Check Engine Light (CEL) illuminated on the dashboard.
• Poor engine performance or reduced fuel efficiency.
• Increased emissions and potential failure of emissions testing.
• Noticeable changes in exhaust temperature readings.

What causes the P205B code?

Common causes of the P205B fault code include:

• A malfunctioning reductant tank temperature sensor.
• Wiring issues such as shorts, breaks, or corrosion in the sensor circuit.
• Defective engine control module (ECM) or problems with its software.
• Contamination of the diesel exhaust fluid, leading to erroneous readings.

How to fix P205B?

To resolve the P205B fault code, consider the following steps:

• Perform a visual inspection of the reductant tank temperature sensor and its wiring for damage or corrosion.
• Test the sensor using a multimeter to ensure it operates within specifications.
• Replace the faulty sensor if necessary.
• Clear the fault code and perform a test drive to determine if the issue persists. If it does, further diagnostics on the ECM may be needed.