CAN communication circuits consist of two data lines (high and low) along with terminating resistors. The PCM, TCCM, TCM, and ABS ECUs are networked via CAN.
PCM, TCCM, TCM and ABS communicate their information to control Engine, Transmission and Brake.
DTC U0121 is set if TCCM can’t receive any response signal from ABS
Item | Detecting Condition | Possible cause |
DTC Strategy |
•
CAN Signal Check |
•
Poor Connection
•
Power supply to each module
•
Open or short in CAN communication line of PCM
•
Open or short in CAN communication line of TCCM
•
Faulty 120Ω registor(Cluster)
•
Faulty PCM
•
Faulty ABS |
Enable Conditions |
•
IG ON | |
Threshold value |
•
No CAN message from ABS for more than 1sec. | |
MIL ON Condition |
•
Lamp ON |
