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    Fault Codes
    VOLVO
    ECM-621D
    VOLVO

    ECM-621D - Engine cooling fan (FC). Signal too low

    System

    Engine Control Module (ECM)

    Volvo models this fault code applies to

    Applies to the following models:

    4 models

    C30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)

    Show models by year and engine (9)
    • Volvo C30 (2007–2013)2007Engine B5254T3 only
    • Volvo C30 (2007–2013)2008–2013Engine B5254T7 only
    • Volvo C70 (2006–2013)2006–2007Engine B5254T3 only
    • Volvo C70 (2006–2013)2008–2013Engine B5254T7 only
    • Volvo S40 (2004–2013)2005–2007Engine B5254T3 only
    • Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
    • Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
    • Volvo V50 (2004–2013)2005–2007Engine B5254T3 only
    • Volvo V50 (2004–2013)2008–2012Engine B5254T7 only

    What does this fault code mean?

    The engine control module (ECM) has registered a fault on the signal cable to the cooling fan control module, where the signal is too low. The cause may be that the signal or supply cable is short-circuited to ground, or that the control module is damaged.

    Possible causes

    • Signal cable short-circuited to ground
    • Supply cable short-circuited to ground
    • Damaged cooling fan control module

    What you can do

    1. 1Check the fuse for the cooling fan circuit
    2. 2Use a multimeter to check whether the cable to the fan touches ground (the body) when the ignition is on
    3. 3Look for chafed cables that may have touched the bodywork
    4. 4With a diagnostic tool: activate the cooling fan with the ignition on and check that it starts
    5. 5If you find no fault, have a workshop check the cooling fan control module

    Symptoms you may notice1

    • The electric cooling fan does not work

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

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