Advanced Diagnostics

DTC U1220 (34): DC-DC Converter Lost Communication with Battery Condition Monitor (BCM) Module




General Description
The DC-DC converter uses an internal timer to measure the intervals between serial communication data updates. When an update is not done for a specified time, a SCIBD serial communication reception malfunction is detected and the abnormal communication information is sent to the battery condition monitor (BCM) module via SCIDB serial communication.




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




Enable Conditions

Malfunction Threshold
The serial communication data is not updated for at least 2 seconds.

Diagnosis Details

Conditions for illuminating the MIL
When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the PCM and BCM memory.

Conditions for clearing the MIL
The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the diagnostic runs.

The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.