P3832high severityPowertrain
DEF Dosing Valve Stuck Closed
on 2010 Audi Q7 3.0L TDI V6 · AWD
What this code means
The DEF injection valve (dosing valve) that sprays DEF into the exhaust is stuck in the closed position. No DEF is being injected.
Symptoms
- DEF not being consumed (level not dropping)
- NOx emissions elevated
- SCR efficiency code may follow
- Derate warning countdown
- Check Engine Light
- Potential speed limitation
Common causes
- DEF crystallization blocking valve
- Dosing valve solenoid failure
- DEF frozen in valve (cold weather)
- Contaminated DEF clogging valve
- Valve mechanical failure
Diagnostic steps
- Monitor DEF dosing command vs actual injection
- Inspect dosing valve for crystallization
- Test valve solenoid electrically
- Check DEF line heating system
- Attempt to command valve open with scan tool
Repair notes
Replace DEF dosing valve. Clean DEF supply line. Check DEF line heater operation for cold weather crystallization prevention.
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