P3831moderate severityPowertrain
DEF (Diesel Exhaust Fluid) Quality Sensor Malfunction
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The DEF quality sensor that measures urea concentration in the DEF tank is malfunctioning.
Symptoms
- DEF quality warning
- Potential derate countdown
- Check Engine Light
- Unable to verify DEF concentration
- Service DEF system message
Common causes
- DEF quality sensor failure
- Sensor contaminated by crystallized DEF
- Sensor wiring fault
- Sensor connector corrosion
- Diluted or incorrect DEF affecting sensor
Diagnostic steps
- Read DEF quality sensor PID
- Test sensor with known-good DEF
- Inspect sensor for crystallization
- Check sensor wiring and connector
- Compare sensor reading to refractometer test
Repair notes
Replace DEF quality sensor. Clean sensor mounting area of crystallized DEF. Use only API-certified DEF.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1