Szukaj
U0121
System
Network (CAN Bus)
Wymagany skaner
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Lost Communication with ABS Control Module

Understand U0121, common causes, and the right TOPDON scanner to diagnose it.

ABS module not communicating — ABS, stability control, and sometimes cruise may be disabled.

Typowe objawy

  • ABS light on
  • Traction control off
  • C-codes may accompany

Typowe przyczyny

  • ABS module failure
  • Wheel speed sensor wiring damaging comm
  • Low voltage
  • Blown ABS fuse

Jakiego skanera potrzebujesz?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Użyj danych na żywo i freeze frame przed wymianą części. Kody ABS, SRS i U zwykle wymagają skanera full-system.

Wskazówki diagnostyczne

  • Zapisz freeze frame, gdy pojawi się kod
  • Kasuj kod dopiero po usunięciu przyczyny
  • Sprawdź powiązane kody pending
  • Sprawdź, czy napięcie akumulatora jest powyżej 12,4 V przed podejrzeniem czujników

Polecane skanery TOPDON

Często zadawane pytania

What does U0121 mean?
U0121 indicates lost communication with abs control module. ABS module not communicating — ABS, stability control, and sometimes cruise may be disabled.
Can I diagnose U0121 with a basic code reader?
U0121 may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Which TOPDON scanner do I need for U0121?
Full-system scanner (engine, ABS, SRS, transmission, service resets) See recommended tools on this page.
Is it safe to drive with U0121?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.