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P20F2 Code - SCR NOx Catalyst Efficiency Below Threshold Bank 2

- Code Popularity: 3,336 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC P20F2?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty NOx Sensor
  • Diesel Exhaust Fluid
  • Faulty Selective Catalyst Reduction (SCR) Catalyst
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How to Fix the DTC P20F2?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P20F2 code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P20F2 Description

The Selective Catalyst Reduction (SCR) catalyst is monitored to ensure it is capable of NOx conversion. The concentration of NOx upstream of the SCR is calculated based on a model. NOx concentration downstream of the SCR is measured with a NOx sensor. Using these concentrations, the cumulative efficiency of the SCR catalyst is calculated and compared to a threshold. If the cumulative efficiency is below this threshold for a sufficient period of time, a fault will be indicated.
The reductant, Diesel Exhaust Fluid (DEF), which is used as part of the SCR catalyst reaction, is monitored to ensure the tank is not refilled with an improper reductant. Upon detection of a refill event, the monitor is activated. After the SCR Catalyst Efficiency Monitor has completed and the SCR has been determined to be functional, the efficiency monitor continues to calculate the cumulative efficiency of the system. Each subsequent value for cumulative efficiency is included in two filtering routines, one for short term efficiency and the other for long term efficiency. If the difference between the two filtered efficiencies becomes greater than a threshold, a fault is indicated. the short term efficiency needs to be less than 0.20 and the delta between short and long term efficiency needs to be greater than 0.10.

OBDII Code P20F2 - SCR NOx Catalyst Efficiency Below Threshold Bank 2 - AutoCodes.com
P20F2 Code - SCR NOx Catalyst Efficiency Below Threshold Bank 2

Need More Information on the Code?

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Information for Specific Makes

  • P20F2 Dodge SCR NOx Catalyst Efficiency Below Threshold Bank 2
  • P20F2 Ford SCR NOx Catalyst Efficiency Below Threshold Bank 2

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Code P20F2 comments

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