P0405moderate severityPowertrain
EGR Sensor A Circuit Low
on 2021 Audi A6 3.0L Turbo V6 · AWD
What this code means
Low voltage from the EGR position sensor A.
Symptoms
- Check Engine Light
- EGR control issues
Common causes
- Short to ground in sensor circuit
- Faulty sensor
- Wiring damage
Diagnostic steps
- Test sensor voltage
- Check for shorts
- Inspect wiring
Repair notes
Repair wiring or replace EGR valve (sensor often integrated).
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