The P202E: Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 1 refers to an issue with the performance or range of the reductant injection valve responsible for dosing DEF (Diesel Exhaust Fluid) into the exhaust system. This could be due to a faulty valve, wiring issues, or connector problems affecting its operation.
P202E – Quick Overview
Code | Information |
---|---|
Meaning | P202E: Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 1 |
Is it serious? | Yes, this issue can reduce the effectiveness of the SCR (Selective Catalytic Reduction) system, potentially leading to higher NOx emissions and failing emissions tests. |
Possible causes | – Faulty reductant injection valve – Incorrect valve performance – Wiring or connector issues |
How to diagnose? | – Test the reductant injection valve for range and performance – Inspect wiring and connectors – Verify valve operation |
P202E Meaning
The P202E: Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 1 code indicates that the reductant injection valve for Bank 1 Unit 1 is not operating within the expected performance range. This valve injects DEF into the exhaust to reduce NOx emissions. A fault in the valve or its control circuit can impair the vehicle’s emission control system, leading to increased emissions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to look for additional codes related to the reductant system or emission control components. These codes may offer further insight into the issue. | OBD-II Scanner |
Test the Reductant Injection Valve | Use a diagnostic tool to test the operation of the reductant injection valve for Bank 1 Unit 1. Ensure it is opening and closing as expected, and delivering the correct amount of reductant. | Diagnostic Tool |
Inspect Wiring and Connectors | Visually inspect the wiring and connectors leading to the reductant injection valve. Look for any damage, corrosion, or loose connections that could be affecting the valve’s performance. | Flashlight, Multimeter |
Check for Valve Blockages | Inspect the reductant valve and its lines for blockages or restrictions that could impair DEF delivery. Clean or replace any blocked components as necessary. | Flashlight, DEF Cleaning Solution |
Test Valve Circuit Continuity | Use a multimeter to check for continuity in the wiring circuit connected to the reductant valve. Make sure there are no shorts or open circuits that could affect valve operation. | Multimeter |
Verify Valve Calibration | Ensure the reductant injection valve is properly calibrated using a diagnostic tool. If the valve is out of calibration, it may need to be adjusted or replaced. | Diagnostic Tool |
Repair or Replace Faulty Components | If the valve, wiring, or connectors are damaged or faulty, repair or replace them to restore proper operation of the reductant injection valve. | Wiring Repair Kit, Valve Replacement |
Clear the Code and Test Drive | After repairs are made, clear the P202E code using an OBD-II scanner. Take the vehicle for a test drive to confirm that the valve is working properly and the issue has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to verify that the P202E code has not returned. | 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)