Reductant Pressure Too Low
The system is detecting low pressure in the reductant system.
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 car has a system that injects a fluid to reduce harmful emissions. This code means that the pressure of that fluid is not high enough to do its job properly.
What the computer is actually seeing
The engine control module (ECM) monitors the pressure in the reductant system, which should be above 5 psi during operation. A reading below that indicates a fault.
What a healthy reading looks like
Reductant pressure should be between 5-10 psi during normal 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.
- 1Inspect the wiring and connectors to the reductant pressure sensor for damage or corrosion. Repair any issues found.
- 2Check the reductant fluid level; it should be above the minimum mark.
- 3If fluid is low, top it off with the correct reductant (typically DEF) and clear the code. Drive the vehicle to see if the code returns.
- 4Test the resistance of the reductant pressure sensor with a multimeter. Expected resistance should be close to specifications (check service manual for specific numbers). Replace if out of spec.
- 5Use a scan tool to monitor the pressure readings while operating the vehicle. Confirm it’s within the expected range of 5-10 psi. If not, suspect a faulty sensor or pump.
Common causes
- Faulty pressure sensor
- Leaking reductant lines or connections
- Clogged filter in the reductant system
- Damaged pump not generating proper pressure
Typical repair cost
$$
Related codes
Frequently asked questions
Can I still drive the vehicle?
It's drivable but you will have reduced efficiency and possibly increased emissions. Fix it soon.
Will this code come back after clearing?
If the issue isn't fixed, it will likely return.
Why does this code appear with other codes?
It often pairs with codes related to the emission control system or reductant issues.
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