VOLVO
ECM-0405 - Position sensor (exhaust gas recirculation (EGR)). Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (10)
- Volvo C30 (2007–2013)2007Engine D4204T only
- Volvo C30 (2007–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo C70 (2006–2013)2008Engine D4204T only
- Volvo C70 (2006–2013)2009–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo S40 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo S40 (2004–2013)2007Engine D4204T only
- Volvo S40 (2004–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
- Volvo V50 (2004–2013)2004–2006Engine D4204T, D4204T2 only
- Volvo V50 (2004–2013)2007Engine D4204T only
- Volvo V50 (2004–2013)2008–2010Engine D4204T only · Transmission MMT6, MPS6 only
What does this fault code mean?
The control module monitors the EGR valve function, and the position sensor in the valve should report a position that matches the control. If the signal from the position sensor is too low, the fault is set. The causes are a signal wire shorted to ground or a damaged EGR valve.
Possible causes
- Signal wire short-circuited to ground
- Damaged EGR valve
What you can do
- 1Switch off the ignition and check the connections between the control module and the EGR valve for contact resistance and oxidation
- 2Use a multimeter to check that the signal wire from the position sensor is not shorted to ground
- 3Look for chafed wires near the EGR valve, where the cable may have been pressed against an earthed metal part
- 4If you have a diagnostic tool, read the EGR valve position in live data with the engine running and see whether the value changes when the valve is controlled
- 5If the fault remains, have a workshop with diagnostic equipment check the EGR valve and its position sensor
Symptoms you may notice1
- The check engine lamp lights or behaves abnormally
General guidance for car owners. Diagnosis on the car can point to a different cause.