The P20E8: Reductant Pressure Too Low fault code indicates that the pressure in the reductant (DEF, Diesel Exhaust Fluid) system is below the required level for proper injection. This low pressure can result in ineffective emissions control. The problem may be caused by a faulty pressure sensor, leaks in the reductant lines, or other issues in the reductant delivery system.
P20E8 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P20E8: Reductant Pressure Too Low |
| Is it serious? | Yes, low pressure in the reductant system can affect emissions control, leading to reduced system performance. |
| Possible causes | – Low pressure in the reductant system – Faulty pressure sensor – Leaks in the reductant lines |
| How to diagnose? | – Measure reductant pressure – Test the pressure sensor – Check for leaks in the reductant lines |
P20E8 Meaning
The P20E8 fault code signifies that the pressure in the reductant system is too low to function properly. This low pressure can prevent the Diesel Exhaust Fluid (DEF) from being injected correctly, causing emissions control to fail or underperform. Common causes of low pressure include faulty sensors, leaks in the lines, or blockages in the reductant delivery system.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any additional codes that might provide further details on the reductant pressure issue. | OBD-II Scanner |
| Measure Reductant Pressure | Use a pressure gauge to measure the pressure in the reductant system and ensure it meets the manufacturer’s specified range. | Pressure Gauge |
| Test the Pressure Sensor | Use a diagnostic tool to test the functionality of the reductant pressure sensor to verify that it is providing accurate readings. | Multimeter, Diagnostic Tool |
| Inspect for Leaks in the Reductant Lines | Visually inspect the reductant lines for any signs of leaks, cracks, or damage that could cause a reduction in pressure. | Flashlight, Leak Detection Fluid |
| Repair or Replace Faulty Components | If leaks are found or the sensor is faulty, repair or replace the components as needed to restore the correct reductant pressure. | 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 ensure the issue has been resolved. | OBD-II Scanner, Vehicle Manual |
| Recheck for Codes | After the test drive, rescan the vehicle to ensure the P20E8 code does not return. | OBD-II Scanner |
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