DTC U0104 (A/T System)
DTC U0104 : F-CAN Malfunction (TCM - Millimeter Wave Radar)
General Description
The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (CAN_H and CAN_L). When the information is not sent from the millimeter wave radar via the F-CAN lines and this condition continues for a specified time or when the information sent from the millimeter wave radar is abnormal and this condition continues for a specified cycle, the transmission control module (TCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 2 seconds or more |
| DTC Type | One drive cycle, MIL off, shift position indicator blinks |
Enable Conditions
| Condition | |
|---|---|
| Vehicle | ON mode |
Malfunction Threshold
One of these conditions is met:
- The TCM does not receive any signals from the millimeter wave radar via F-CAN lines for at least 1 second.
- The information sent from the millimeter wave radar is abnormal at least 100 times.
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- F-CAN circuit F-CAN A_H line open
- F-CAN circuit F-CAN A_L line open
- F-CAN circuit F-CAN A_H line short to ground
- F-CAN circuit F-CAN A_L line short to ground
- F-CAN circuit F-CAN B_H line open
- F-CAN circuit F-CAN B_L line open
- F-CAN circuit F-CAN B_H line short to ground
- F-CAN circuit F-CAN B_L line short to ground
- F-CAN circuit F-CAN E_H line open
- F-CAN circuit F-CAN E_L line open
- F-CAN circuit F-CAN E_H line short to ground
- F-CAN circuit F-CAN E_L line short to ground
- Millimeter wave radar internal circuit failure
- TCM internal circuit failure
Confirmation Procedure
Operating Condition
Turn the vehicle to the ON mode, and wait for several seconds.
With the HDS
None.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the shift position indicator blinks and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory. The MIL does not come on.
Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.