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    VOLVO
    ECM-P042009
    VOLVO

    ECM-P042009 - Catalyst System Efficiency Below Threshold (Bank 1). General Failure Information. Component Failures

    System

    Engine Control Module (ECM)

    Volvo models this fault code applies to

    Applies to the following models:

    7 models

    S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V70 (2008–), XC60 (2009–)

    Show models by year and engine (20)
    • Volvo S60 (2011–)2011Engine B4164T, B4164T3, B4204T6, B4204T7 only
    • Volvo S60 (2011–)2012–2014Engine B4164T, B4164T2, B4164T3, B4204T7 only
    • Volvo S60 (2011–)2015Engine B4164T, B4164T2, B4164T3 only
    • Volvo S80 (2007–)2010Engine B4204T6 only
    • Volvo S80 (2007–)2011Engine B4164T, B4204T6, B4204T7 only
    • Volvo S80 (2007–)2012–2014Engine B4164T, B4164T2, B4204T6, B4204T7 only
    • Volvo S80 (2007–)2015Engine B4164T only
    • Volvo V40 (2013–)2013Engine B4164T, B4164T3 only
    • Volvo V40 (2013–)2014–2015Engine B4164T, B4164T3, B4164T4 only
    • Volvo V40 Cross Country (2013–)2013–2015Engine B4164T only
    • Volvo V60 (2011–)2011Engine B4164T, B4164T3, B4204T6, B4204T7 only
    • Volvo V60 (2011–)2012–2014Engine B4164T, B4164T2, B4164T3, B4204T7 only
    • Volvo V60 (2011–)2015Engine B4164T, B4164T2, B4164T3 only
    • Volvo V70 (2008–)2010Engine B4204T6 only
    • Volvo V70 (2008–)2011Engine B4164T, B4204T6, B4204T7 only
    • Volvo V70 (2008–)2012–2014Engine B4164T, B4164T2, B4204T7 only
    • Volvo V70 (2008–)2015Engine B4164T, B4164T2 only
    • Volvo XC60 (2009–)2010Engine B4204T6 only
    • Volvo XC60 (2009–)2011–2012Engine B4204T6, B4204T7 only
    • Volvo XC60 (2009–)2013–2015Engine B4204T7 only

    What does this fault code mean?

    The code concerns the catalytic converter efficiency on bank 1 and is a component fault code. The ECM continuously compares the signal from the rear oxygen sensor with the front one, and the code is set when catalytic converter efficiency deviates too much.

    Possible causes

    • Misfiring
    • Leakage in the intake system
    • Leakage in the exhaust system
    • Faulty fuel pressure
    • Uneven compression
    • Damaged catalytic converter

    What you can do

    1. 1Look for air leaks in the intake system, for example at hoses
    2. 2Look for leakage in the exhaust system, particularly at joints and seams
    3. 3If you have a diagnostic tool, read the fault status with the engine running and see whether the fault is active
    4. 4Have a workshop check the fuel pressure and the engine compression, since this needs measuring
    5. 5If the fault check finds nothing, have a workshop judge whether the catalytic converter needs replacing

    Symptoms you may notice1

    • The Check engine (malfunction indicator) light comes on or behaves abnormally

    What the fault can affect1

    • Rear oxygen sensor control is switched off

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

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