VOLVO
ECM-2A20 - Particulate trap. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
8 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), S60 (2001–2009), V50 (2004–2013), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
Show models by year and engine (20)
- Volvo C30 (2007–2013)2007Engine D5244T8, D5244T9 only
- Volvo C30 (2007–2013)2008–2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo C70 (2006–2013)2007Engine D5244T8, D5244T9 only
- Volvo C70 (2006–2013)2008–2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo S40 (2004–2013)2006Engine D5244T8 only
- Volvo S40 (2004–2013)2007Engine D5244T8, D5244T9 only
- Volvo S40 (2004–2013)2008–2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo S60 (2001–2009)2006Engine D5244T4, D5244T5, D5244T6, D5244T7 only
- Volvo S60 (2001–2009)2007–2009Engine D5244T4, D5244T5, D5244T7 only
- Volvo V50 (2004–2013)2006Engine D5244T8 only
- Volvo V50 (2004–2013)2007Engine D5244T8, D5244T9 only
- Volvo V50 (2004–2013)2008–2010Engine D5244T13, D5244T8, D5244T9 only
- Volvo V70 (2000–2008)2006Engine D5244T4, D5244T5, D5244T6, D5244T7 only
- Volvo V70 (2000–2008)2007Engine D5244T4, D5244T5, D5244T7 only
- Volvo V70 (2000–2008)2008Engine D5244T5, D5244T7 only
- Volvo V70 XC / XC70 (2001–2007)2006–2007Engine D5244T4 only
- Volvo XC90 (2003–)2006–2007Engine D5244T4 only
- Volvo XC90 (2003–)2008–2010Engine D5244T4, D5244T5 only
- Volvo XC90 (2003–)2011Engine D5244T18, D5244T4, D5244T5 only
- Volvo XC90 (2003–)2012Engine D5244T18, D5244T5 only
What does this fault code mean?
The engine control module (ECM) compares the pressure before and after the particulate trap. The fault code is set when the signal from the particulate trap pressure sensor is too low, which can be caused by the signal wire being short-circuited to ground or by the particulate trap being missing.
Possible causes
- Signal wire short-circuited to ground
- Particulate trap missing
- Damaged differential pressure sensor
What you can do
- 1Make sure the pressure sensor hoses are not swapped round
- 2Check that the particulate trap is present and fitted correctly
- 3If you have a diagnostic tool: read the pressure sensor value in live data with the engine running and see whether it changes when the engine is revved
- 4Use a multimeter to check that the signal wire to the pressure sensor has no contact with ground (the body)
- 5If the fault remains, have a workshop check the pressure sensor and the particulate trap
Symptoms you may notice2
- Poor performance
- The malfunction indicator light (MIL) comes on
What the fault can affect1
- Engine output and engine speed are limited
General guidance for car owners. Diagnosis on the car can point to a different cause.