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Utrata komunikacji z ECM (sterownik silnika)
Komunikacja sieciowa
Sprawdź szczegóły →B1120
ŚredniCode B1120 indicates a fault in the body system – most often related to the brake booster vacuum sensor (BBV) circuit or electronic body control systems. Diagnosis depends on the vehicle manufacturer.
OBD-II (EN): Brake Booster Vacuum Sensor Circuit Fault
Code B1120 is a body category error that most often indicates a problem with the Brake Booster Vacuum (BBV) sensor or a fault in the Body Control Module – depending on the vehicle manufacturer. Symptoms may include incorrect operation of the ABS system, brake assist, or electronic systems. We recommend immediate diagnosis at a workshop equipped with a professional OBD scanner.
Symptoms
CHECK ENGINE light or body system warning illuminates; possible incorrect operation of the ABS system or electronic brake assist; in GM vehicles, problems with the audio system may occur; reduced braking effectiveness or loss of assist; unstable operation of electronic suspension or steering systems.
Possible causes
• Faulty or contaminated Brake Booster Vacuum (BBV) Sensor • Open circuit or short circuit in the BBV sensor electrical circuit • Low supply voltage to the Body Control Module (BCM) • Fault in the Body Control Module (BCM) or ABS module • In GM vehicles (Chevrolet, GMC, Cadillac): damage to audio output #10 in the body module
Affected systems
Body Control Module (BCM)Układ hamulcowy / ABSCzujnik podciśnienia wspomagania hamulców (BBV)Elektroniczne zawieszenieSystem audio (GM)
Related codes
Code B1120 appears in these brands
Go to messages and symptoms for your brand — there we analyze this code together with other typical alerts.
Does code B1120 require professional diagnostics?
The code alone is not enough. To find the cause, you need to read live data, check freeze frame conditions, and compare with vehicle behavior. Book a diagnostic session.