MechanicDB

📡 CAN Network & Communication Trouble Codes (U-Codes)

Complete diagnostic directory of verified Network trouble codes. Click any code below for full technical anatomy, DIY safety analysis, probability-ranked repair procedures, parts cost estimates, and required aftermarket parts.

Code Description Fault Family Standard Repairs
U0100 Lost Communication With ECM/PCM A lost_comm_powertrain_module SAE Standard 4 fixes
U0101 Lost Communication With TCM lost_comm_powertrain_module SAE Standard 4 fixes
U0121 Lost Communication With Anti-Lock Brake System (ABS) Control Module A lost_comm_chassis_abs_module SAE Standard 4 fixes