The P20F0: SCR NOx Catalyst – Over Temperature Bank 2 fault code indicates that the SCR (Selective Catalytic Reduction) NOx catalyst in Bank 2 is experiencing temperatures higher than normal operating levels. This can lead to damage to the catalyst and a reduction in its ability to control NOx emissions. The issue may be caused by a faulty temperature sensor, problems within the catalyst, or issues in the exhaust system.
P20F0 – Quick Overview
Code | Information |
---|---|
Meaning | P20F0: SCR NOx Catalyst – Over Temperature Bank 2 |
Is it serious? | Yes, excessive temperature can damage the catalyst, reducing NOx emissions control and potentially causing further system damage. |
Possible causes | – High temperature in the SCR NOx catalyst for Bank 2 – Faulty temperature sensor – Issues with the catalyst or exhaust system |
How to diagnose? | – Measure the temperature of the SCR NOx catalyst – Test the temperature sensor – Inspect the catalyst and exhaust system |
P20F0 Meaning
The P20F0 fault code means that the SCR NOx catalyst in Bank 2 is operating at a higher temperature than expected. This could lead to damage to the catalyst, reducing its ability to manage NOx emissions. The problem could be due to a malfunctioning temperature sensor, blockages, or issues within the exhaust system causing excessive heat.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any additional related codes that may provide further insight into the over-temperature condition. | OBD-II Scanner |
Measure the Temperature of the SCR NOx Catalyst | Use a diagnostic tool or an infrared thermometer to measure the temperature of the SCR NOx catalyst in Bank 2 and verify the high-temperature condition. | Diagnostic Tool, Infrared Thermometer |
Test the Temperature Sensor | Use a multimeter to test the functionality of the temperature sensor and ensure it is reading the correct temperature. | Multimeter, Diagnostic Tool |
Inspect the Catalyst and Exhaust System | Visually inspect the SCR NOx catalyst and exhaust system for blockages, cracks, or damage that could be causing excessive heat. | Flashlight, Diagnostic Tool |
Repair or Replace Faulty Components | If the temperature sensor is faulty or damage is found in the exhaust or catalyst system, repair or replace the affected components. | Replacement Parts, Tools |
Clear the Code and Test Drive | After completing repairs, clear the code using an OBD-II scanner and test drive the vehicle to confirm the issue is resolved. | OBD-II Scanner, Vehicle Manual |
Recheck for Codes | After the test drive, rescan the vehicle to ensure the P20F0 code does not return. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)