Fix P20E6: STEP-BY-STEP diagnostic GUIDE!

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

CodeInformation
MeaningP20E6: 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

ActionDescriptionTools Needed
Check for Other CodesUse 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 SystemUse 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 ValveUse 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 LeaksVisually 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 ComponentsIf 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 DriveAfter 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 CodesAfter the test drive, rescan the vehicle to ensure the P20E6 code does not return.OBD-II Scanner
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