Aftertreatment SCR Pressure Sensor
Indicates a problem with the SCR pressure sensor reading.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The pressure sensor measures the pressure in the Selective Catalytic Reduction (SCR) system, which helps reduce emissions. If this sensor fails, the computer can't get accurate readings, and you could fail emissions tests or see performance issues.
What the computer is actually seeing
The engine control module (ECM) expects the SCR pressure to be within a certain range under normal operating conditions—typically around 0.5 to 3.5 PSIG. If the pressure reading is too high or too low, the ECM triggers the fault code.
What a healthy reading looks like
Normal SCR pressure values should be between 1.0 and 2.5 PSIG during active operation.
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. Inspect wiring and connectors to the SCR pressure sensor. Look for frays, breaks, or corrosion. Are they in good condition? (Yes: go to step 2, No: repair or replace wiring/connectors.)
- 22. Check for exhaust leaks in the SCR system. Use a smoke machine if necessary. Are there leaks? (Yes: repair leaks, No: go to step 3.)
- 33. Using a scan tool, monitor the SCR pressure sensor values. Are they within the expected range (1.0 to 2.5 PSIG)? (Yes: possible ECM issue, No: go to step 4.)
- 44. Replace the SCR pressure sensor. Re-check the values. Do they now read within the expected range? (Yes: diagnostic complete, No: check ECM or further diagnostics required.)
Common causes
- Faulty SCR pressure sensor
- Wiring issues or bad connectors
- Exhaust leaks in SCR system
- Contaminated sensor from urea
- ECM software issues
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix this soon. While you can drive, it may affect emissions and could lead to other issues.
Will this code come back after reset?
If the underlying problem isn't fixed, yes, the code will likely return.
Why does this relate to other codes?
The SCR system is interconnected; issues with one component often lead to others due to shared functions.
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