Skip to content
    OBD Tuning
    Send to us
    Send to us
    Home
    Fault Codes
    VOLVO
    CEM-4F42
    VOLVO

    CEM-4F42 - Seat belt buckle, rear right-hand. Faulty signal

    System

    Central Electronic Module (CEM)

    Volvo models this fault code applies to

    This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.

    Applies to the following models:

    5 models

    C30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)

    Show models by year and engine (5)
    • Volvo C30 (2007–2013)2007–2013
    • Volvo C30 Electric (2011–2013)2011–2013
    • Volvo C70 (2006–2013)2006–2013
    • Volvo S40 (2004–2013)2004–2012
    • Volvo V50 (2004–2013)2004–2012

    What does this fault code mean?

    The CEM monitors the right rear belt buckle. If the signal level is faulty, the code is set. The information lamp may light and a message may appear in the display. The fault may lie in the signal wire or in the buckle.

    Possible causes

    • A damaged signal wire between the rear right seat belt buckle and the CEM
    • A faulty seat belt buckle

    What you can do

    1. 1Safety: the seat belt system is part of the crash protection. Do not work on the wiring or the buckle yourself. Have a workshop check it
    2. 2Look for chafed or pinched cables at the rear right seat belt, without removing anything
    3. 3Latch and unlatch the belt several times and see whether the information lamp changes. If it does not, the fault is probably permanent
    4. 4After the work, clear the code and check that the information lamp goes out

    Symptoms you may notice2

    • The information lamp is lit
    • A message appears in the display

    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.