The P20E6: Reductant Injection Air Pressure Too Low fault code indicates that the air pressure in the reductant injection system is below the required level. This can affect the ability of the system to inject reductant effectively, leading to issues with emissions control. The cause could be a faulty air pressure control valve, leaks in the pressure lines, or other system malfunctions.
P20E6 – Quick Overview
Code | Information |
---|---|
Meaning | P20E6: Reductant Injection Air Pressure Too Low |
Is it serious? | Yes, low air pressure can result in poor reductant injection, affecting emissions control and engine performance. |
Possible causes | – Low air pressure in the reductant injection system – Faulty air pressure control valve – Leaks in the pressure lines |
How to diagnose? | – Measure air pressure in the reductant system – Test the air pressure control valve – Inspect pressure lines for leaks |
P20E6 Meaning
The P20E6 fault code means that the air pressure in the reductant injection system is lower than expected. This can cause inefficient injection of the reductant (typically DEF, Diesel Exhaust Fluid), affecting the vehicle’s ability to manage emissions. Potential causes include leaks in the pressure lines, a malfunctioning air pressure control valve, or other system failures.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any related codes that might provide additional insight into the low air pressure issue. | OBD-II Scanner |
Measure Air Pressure in the Reductant System | Use a pressure gauge to measure the air pressure in the reductant injection system and verify it matches the manufacturer’s specifications. | Pressure Gauge |
Test the Air Pressure Control Valve | Use a diagnostic tool to test the air pressure control valve and ensure it is functioning correctly by regulating the correct amount of pressure. | Diagnostic Tool, Multimeter |
Inspect Pressure Lines for Leaks | Visually inspect the pressure lines for signs of leaks, cracks, or damage that could be causing a reduction in air pressure. | Flashlight, Leak Detection Fluid |
Repair or Replace Faulty Components | If leaks or faulty components are found (such as the pressure control valve or lines), repair or replace them to restore proper air pressure. | Replacement Parts, Tools |
Clear the Code and Test Drive | After 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 P20E6 code does not return. | OBD-II Scanner |

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