DPF Differential Pressure Sensor Out of Range
The diesel particulate filter (DPF) differential pressure sensor is reporting values outside of normal range.
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What it means (plain English)
The DPF pressure sensor measures the difference in pressure before and after the DPF to determine how clogged it is. If this reading is outside the norm, it usually means the DPF is either too dirty or there's a problem with the sensor itself.
What the computer is actually seeing
The ECM compares the pressure readings and expects them to stay within the range of 0-5 volts from the sensor. If it sees values outside of these limits, it throws this code.
What a healthy reading looks like
Normal DPF differential pressure should be around 0-3 inches of water column at idling and increase to 5-15 inches under heavy load.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring and connector to the DPF differential pressure sensor for signs of damage or corrosion. If damaged, repair or replace the wiring as needed. Decision: If wiring is good, move to step 2.
- 22. Measure the output voltage of the DPF differential pressure sensor while the engine is running. You should see 0-5 volts depending on the engine load. Decision: If voltage is out of range, replace the sensor. If within range, move to step 3.
- 33. Inspect the DPF for clogs or excessive soot accumulation. If the DPF is clean but still throwing the code, replace the sensor. Decision: If DPF is clogged, perform a DPF regeneration or replace the DPF.
Common causes
- Clogged DPF
- Faulty differential pressure sensor
- Wiring issues with the sensor
- Exhaust leaks
- Failed ECM
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best not to drive with this code for long, as it can lead to reduced engine performance and potentially cause further issues.
Will this code come back after clearing it?
If the underlying issue isn't fixed (like a clogged DPF or bad sensor), the code will likely return.
Why does this code pair with SPN 3252 and 3253?
These codes are related to the same DPF pressure sensor and help pinpoint specific issues in the sensor circuit or DPF functionality.
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