OBD
P20E6
Reductant Injection Air Pressure Too Low
What it means
P20E6 means Reductant Injection Air Pressure Too Low.
Check these first
- Low air pressure in the reductant injection air supply
- A leak or restriction in the air supply line
- A failed air pressure sensor
- A failed reductant injection air pump
What to do next
- Read reductant injection air pressure on a scan tool
- Check the air supply line for leaks or restriction
- Test the air pressure sensor against a gauge
- Replace the reductant injection air pump if pressure stays low
- Clear the code and retest
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Updated
Generic SAE J2012 definition. Last updated 2026-10-10.