Communication with the anti-lock brake system module has been lost.
Informational only. Consult a qualified mechanic.
ABS and stability control are disabled. Have module and wiring checked.
The U0121 OBD-II diagnostic trouble code (DTC) indicates: lost communication with abs module. This is a high-severity network code that your vehicle's onboard diagnostics system triggers when communication with the anti-lock brake system module has been lost. If your check engine light is on with this code, the vehicle is generally safe to drive, but you should have it inspected soon.
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