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    Fault Codes
    VOLVO
    ECM-220A
    VOLVO

    ECM-220A - Rear heated oxygen sensor (HO2S). Faulty signal

    System

    Engine Control Module (ECM)

    Volvo models this fault code applies to

    Applies to the following models:

    11 models

    C30 (2007–2013), C70 (2006–2013), C70 Cabriolet (1998–2005), C70 Coupé (1998–2002), S40 (2004–2013), S60 (2001–2009), S70 (1997–2000), S80 (1999–2006), V50 (2004–2013), V70 (1997–2000), V70 (2000–2008)

    Show models by year and engine (27)
    • Volvo C30 (2007–2013)2007–2011Engine B5244S4 only
    • Volvo C70 (2006–2013)2006All engines except: B5254T3
    • Volvo C70 (2006–2013)2007–2010Engine B5244S4, B5244S5 only
    • Volvo C70 (2006–2013)2011Engine B5244S4 only
    • Volvo C70 Cabriolet (1998–2005)2000Engine B5244S only
    • Volvo C70 Coupé (1998–2002)1999Engine B5254S DENSO only
    • Volvo C70 Coupé (1998–2002)2000Engine B5244S only
    • Volvo S40 (2004–2013)2004Engine B5244S4, B5244S5 only
    • Volvo S40 (2004–2013)2005–2010Engine B5244S4, B5244S5, B5244S7 only
    • Volvo S60 (2001–2009)2001, 2009Engine B5244S, B5244S2 only
    • Volvo S60 (2001–2009)2002Engine B5244S, B5244S2, B5244SG, B5244SG2 only
    • Volvo S60 (2001–2009)2003–2005Engine B5244S, B5244S2, B5244S6, B5244SG, B5244SG2 only
    • Volvo S60 (2001–2009)2006Engine B5244S, B5244S2, B5244S6, B5244SG only
    • Volvo S60 (2001–2009)2007–2008Engine B5244S, B5244S2, B5244SG only
    • Volvo S70 (1997–2000)1999Engine B5254S DENSO only
    • Volvo S70 (1997–2000)2000Engine B5244S, B5244S2, B5244SG, B5244SG2 only
    • Volvo S80 (1999–2006)1999–2000Engine B5244S, B5244S2 only
    • Volvo S80 (1999–2006)2001, 2006Engine B5244S, B5244S2, B5244SG only
    • Volvo S80 (1999–2006)2002–2005Engine B5244S, B5244S2, B5244SG, B5244SG2 only
    • Volvo V50 (2004–2013)2004Engine B5244S4, B5244S5 only
    • Volvo V50 (2004–2013)2005–2010Engine B5244S4, B5244S5, B5244S7 only
    • Volvo V70 (1997–2000)1999Engine B5254S DENSO only
    • Volvo V70 (1997–2000)2000Engine B5244S, B5244S2, B5244SG, B5244SG2 only
    • Volvo V70 (2000–2008)2001, 2007–2008Engine B5244S, B5244S2, B5244SG only
    • Volvo V70 (2000–2008)2002Engine B5244S, B5244S2, B5244SG, B5244SG2 only
    • Volvo V70 (2000–2008)2003–2005Engine B5244S, B5244S2, B5244S6, B5244SG, B5244SG2 only
    • Volvo V70 (2000–2008)2006Engine B5244S, B5244S2, B5244S6, B5244SG only

    What does this fault code mean?

    The code is set when the rear oxygen sensor does not reach its limit values after a while, even though the sensor heating is on. The cause can be a defective sensor or poor contact in the connections. While the fault is present, control using the rear sensor is switched off and the warning lamp comes on.

    Possible causes

    • Defective rear oxygen sensor
    • Contact resistance or oxidation in the connections

    What you can do

    1. 1Check the connector on the rear oxygen sensor for contact resistance and oxidation
    2. 2Do not use rust solvent spray or grease in the oxygen sensor connector
    3. 3Clear the code and road test the car to see whether it returns
    4. 4If the connector is free of oxidation but the fault remains, have a workshop try a new rear oxygen sensor

    Symptoms you may notice1

    • The malfunction indicator lamp (MIL) comes on

    What the fault can affect1

    • Control using the rear oxygen sensor is switched off

    General guidance for car owners. Diagnosis on the car can point to a different cause.

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