By the AutoDTCs Editorial Team·Researched against SAEJ2012 & factory service data — how we research this
OBD-II Diagnostic Trouble Code
U121F
Display control unit
U
Network
modules / CAN bus
modules / CAN bus
1
Mfr
manufacturer code
manufacturer code
2
Network subsystem
1F
Display control unit
Severity · general guide
Moderate
Module communication fault
Code type
Generic
System
Network