Skip to content
    OBD Tuning
    Send to us
    Send to us
    Home
    Fault Codes
    VOLVO
    ECM-210A
    VOLVO

    ECM-210A - Front 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 ECM checks the front oxygen sensor's signal while closed-loop fuel control is active. If the sensor does not activate, or activates too slowly, the code is set. The cause may be a defective oxygen sensor or poor contact in the connectors.

    Possible causes

    • Defective front oxygen sensor
    • Contact resistance in the connections

    What you can do

    1. 1Read and clear the fault code and check whether it returns
    2. 2Check that the connectors at the oxygen sensor and the engine control module are free from oxidation and contact resistance; do not use penetrating spray or grease on the connector
    3. 3If you have a diagnostic tool, read the oxygen sensor value in live data with the engine running and see whether it changes
    4. 4If the connectors are in good condition but the fault remains, have a workshop check the oxygen sensor

    Symptoms you may notice1

    • The malfunction indicator lamp (MIL) is lit

    What the fault can affect1

    • Fuel trim control is switched off

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

    OBD Tuning

    Sweden's leading expert center for automotive electronics. We offer professional ECU tuning, control unit repair and diagnostics with 12-month warranty.

    Services

    • Engine Tuning
    • ECU Repair
    • Module Cloning
    • Instrument Cluster
    • SRS / Airbag
    • Immobilizer

    Database & Diagnostics

    • ECU Database
    • DTC Fault Code Catalog
    • Diagnostic Guides & Live Data
    • AI Fault Code Analyzer
    • News

    ECU Manufacturers

    • Bosch
    • Continental
    • Delphi
    • Delco
    • Denso
    • Magneti Marelli
    • Siemens / VDO
    • Keihin
    • Temic

    Company

    • About us
    • Contact
    • Workshop Partners
    • Shipping Guide
    • Warranty
    • FAQ
    • Terms & Conditions
    • Privacy Policy
    • Site Map

    • Engine Tuning
    • ECU Repair
    • Module Cloning
    • Instrument Cluster
    • SRS / Airbag
    • Immobilizer

    • ECU Database
    • DTC Fault Code Catalog
    • Diagnostic Guides & Live Data
    • AI Fault Code Analyzer
    • News

    • Bosch
    • Continental
    • Delphi
    • Delco
    • Denso
    • Magneti Marelli
    • Siemens / VDO
    • Keihin
    • Temic

    • About us
    • Contact
    • Workshop Partners
    • Shipping Guide
    • Warranty
    • FAQ
    • Terms & Conditions
    • Privacy Policy
    • Site Map

    Visit us

    Gjuterigatan 29, Karlstad

    Call us

    054-830 480

    Email us

    service@obdtuning.se

    © 2026 OBD Tuning Karlstad. All rights reserved.