U0121Lost Communication With Anti-Lock Brake System (ABS) Control Module
Voici ce que signifie le code défaut U0121, pourquoi il apparaît et que faire à son sujet.
Système: Network / module communication
Évitez de rouler — ce défaut peut être dangereux ou causer davantage de dommages. Faites-le contrôler sans attendre.
Ce que signifie U0121
A module on the communication network has stopped receiving messages from the ABS (anti-lock brake) control module. In practice, the car can no longer communicate with the system that manages anti-lock braking and usually traction/stability control. Normal braking generally still works, but the safety-assist features (ABS, traction control, stability control) are typically disabled. It is often caused by lost power to the ABS module or a network wiring problem.
Symptômes courants
- ABS warning light on
- Traction control / stability control (ESC) light on
- Check engine light may be on
- ABS and stability features disabled
- Speedometer may be inaccurate or dead on some vehicles
Causes courantes
Classées de la plus courante à la moins courante.
- 1Loss of power or ground to the ABS module (blown fuse, corroded connector)
- 2Damaged, broken, or shorted CAN bus wiring to the ABS module
- 3Corroded, loose, or backed-out connector pins at the ABS module
- 4Another module disrupting the communication bus
- 5Failed or faulty ABS control module
Que faire
Have this checked soon, because ABS, traction control, and stability control are likely disabled even though basic braking still works. Drive gently and allow extra stopping distance, especially in rain, ice, or hard braking, until it is repaired. A technician will check ABS module power, grounds, and the network wiring before replacing parts.
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Questions fréquentes
Que signifie le code U0121 ?
A module on the communication network has stopped receiving messages from the ABS (anti-lock brake) control module. In practice, the car can no longer communicate with the system that manages anti-lock braking and usually traction/stability control. Normal braking generally still works, but the safety-assist features (ABS, traction control, stability control) are typically disabled. It is often caused by lost power to the ABS module or a network wiring problem.
Quelles sont les causes du code U0121 ?
Les causes les plus courantes sont : Loss of power or ground to the ABS module (blown fuse, corroded connector), Damaged, broken, or shorted CAN bus wiring to the ABS module, Corroded, loose, or backed-out connector pins at the ABS module, Another module disrupting the communication bus, Failed or faulty ABS control module.
Peut-on rouler sans danger avec le code U0121 ?
Évitez de rouler — ce défaut peut être dangereux ou causer davantage de dommages. Faites-le contrôler sans attendre.
Comment corriger le code U0121 ?
Have this checked soon, because ABS, traction control, and stability control are likely disabled even though basic braking still works. Drive gently and allow extra stopping distance, especially in rain, ice, or hard braking, until it is repaired. A technician will check ABS module power, grounds, and the network wiring before replacing parts.
Ce sont des informations générales pour vous aider à comprendre le code U0121, et non un substitut au diagnostic d’un mécanicien qualifié. Confirmez toujours la cause avant de remplacer des pièces.
Les définitions des codes suivent la liste OBD-II normalisée (SAE J2012). CarVinVin est indépendant et n’est affilié à aucun constructeur.