Genuine Diesel Particulate Filter (DPF) Differential Pressure Sensor Fault
Indicates a problem with the differential pressure sensor in the DPF system.
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What it means (plain English)
The differential pressure sensor monitors the difference in pressure before and after the DPF to check for clogging. If it's failing, the engine doesn’t know how blocked the DPF is, which can lead to a no-start condition or engine limp mode.
What the computer is actually seeing
The engine control module (ECM) checks the voltage output from the DPF pressure sensor. A voltage reading that is too low (below 0.2V) or too high (above 4.8V) indicates a failure.
What a healthy reading looks like
Expected voltage from the differential pressure sensor should be between 0.2V and 4.8V, with typical values around 2.5V at idle with no blockage.
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 connectors to the differential pressure sensor for damage or corrosion. If found, repair as necessary and retest.
- 22. Use a multimeter to measure voltage at the DPF differential pressure sensor. Is the voltage between 0.2V and 4.8V? If no, replace the sensor.
- 33. Inspect the DPF for blockage. A backpressure test can be performed; compare readings before and after the filter. If there is excessive backpressure, replace the DPF.
- 44. If the sensor checks out and the DPF is clear, check the ECM for fault codes or issues. If none exist, further diagnosis may be needed.
Common causes
- Wiring issues in the sensor circuit
- Faulty differential pressure sensor
- Clogged diesel particulate filter (DPF)
- Faulty engine control module (ECM)
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it's not safe. The vehicle may go into limp mode, leading to loss of power and potential safety hazards.
Will this code come back after repair?
If the fault is properly addressed and related components are functioning, it should not return.
Why does this code pair with SPN 3216?
SPN 3216 is related to the DPF filter status and pressure monitoring, often showing up with DP sensor issues.
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