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    Fault Codes
    VOLVO
    ECM-P013A21
    VOLVO

    ECM-P013A21 - O2 Sensor Slow Response - Rich to Lean (Bank 1 and Sensor 2). General Signal Failures. Signal too low

    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?

    Although the code is named for a low signal, it concerns the rear oxygen sensor in bank 1, sensor 2, which shows a lean mixture too late. The engine control module (ECM) checks the sensor and changes the mixture if the sensor does not show lean. At fuel cut-off the sensor should show a lean mixture, and if the switch takes too long the code is set.

    Possible causes

    • Leak in the exhaust system
    • Damaged rear oxygen sensor

    What you can do

    1. 1Read the code, clear it and road test the car to see whether it comes back
    2. 2Check the exhaust system for air leaks; a leak before the rear sensor can give a wrong signal
    3. 3Check the connector to the rear sensor and do not use rust solvent spray or grease in it
    4. 4If no leak is found, try a new rear oxygen sensor, as a damaged sensor can also set the code

    Symptoms you may notice1

    • Check engine light (MIL) on

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

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