Code C1120 appears in these brands
Go to messages and symptoms for your brand — there we analyze this code together with other typical alerts.
C1120
WysokiFault in the left front ABS solenoid valve (inlet). Problem with hydraulic pressure regulation in the anti-lock braking system.
OBD-II (EN): Front Left ABS Solenoid Fault (Input)
Code C1120 signals a problem with the left front ABS solenoid valve, which is responsible for regulating brake pressure to prevent wheel lock-up. The cause may be a faulty valve, an open circuit in the wiring harness, or poor contact in the ABS module connector. Due to the direct impact on braking performance, urgent diagnosis at a workshop is recommended.
Symptoms
• ABS warning light is on the dashboard • ESP/ESC warning light may illuminate • ABS system may be inactive during braking • Possible locking of the left front wheel during hard braking • In some vehicles (Mercedes ML), spontaneous braking of one wheel
Possible causes
• Damaged left front wheel ABS solenoid valve • Open or short circuit in the ABS solenoid valve wiring harness • Poor electrical contact in the ABS module/controller connector • Damaged ABS controller (hydraulic module) • Contamination or corrosion of ABS system electrical connectors
Affected systems
Does code C1120 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.