DTC U0599 (Battery Condition Monitor Module)
DTC U0599: DC-DC Converter Serial Communication Receive Error
General Description
The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (H line and L line). When the battery condition monitor module does not receive the signal from the DC-DC converter via the F-CAN line for a set time, a malfunction is detected and a DTC is stored.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 2.0 seconds or more |
| DTC Type | Two drive cycles, MIL off, POWER SYSTEM indicator on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Elapsed time since the 12 volt battery voltage reaches to a specified value after the vehicle condition is turned to the ON mode | 3 seconds | - |
| 12 volt battery voltage | 10.2 V | - |
Malfunction Threshold
One of these conditions is met for at least 2.0 seconds:
- The battery condition monitor module does not receive any signals via the F-CAN lines.
- The information sent from the DC-DC converter is abnormal.
Possible Cause
NOTE: 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 D_H line open
- F-CAN circuit F-CAN D_L line open
- F-CAN circuit F-CAN D_H line short
- F-CAN circuit F-CAN D_L line short
- DC-DC converter failure
- DC-DC converter does not work
- Battery condition monitor module failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored is the battery condition monitor module memory. If the malfunction returns in the next (second) drive cycle, the POWER SYSTEM indicator comes on and a Confirmed DTC and the freeze data are stored. The MIL does not come on.
Conditions for clearing the DTC
The POWER SYSTEM indicator is cleared if the malfunction does not return in the next trip in which the diagnostic runs. The POWER SYSTEM indicator, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.