A/T System

Advanced Diagnostics - DTC U0104: Lost Communication With Adaptive Cruise Control (ACC) Unit-PCM (A/T System)






General Description
The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (F-CAN A H and F-CAN A L). When the information is not sent from the adaptive cruise control (ACC) unit via the F-CAN A lines and this condition continues for a specified time or when the information sent from the ACC unit is abnormal and this condition continues for a specified cycle, the powertrain control module (PCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
One of these conditions is met:
- The PCM does not receive any signals via the F-CAN A lines for at least 1 second.
- The information sent from the ACC unit is abnormal at least 20 times.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, the D indicator blinks, and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.