VCBATT_a544 — LV Battery Comms Bus Turned Off
Full alert identifier: VCBATT_a544_LVBatteryCommsBusTurnedOff
Message shown in the car
Low voltage (LV) battery communication disabled Low LV battery state of charge - Preserving energy
Alert description
The vehicle controller has disabled communications over the bus that connects to the low voltage (LV) battery after detecting a condition (or conditions) that may cause the LV battery to become overdischarged. To avoid overdischarge that could make the LV battery unrecoverable, do not restore communications until the LV system is fully supported by the Power Conversion System (PCS).
Potential impact
The vehicle controller will have less information about the LV battery until it is serviced. Headlamps and windshield wipers may be unavailable, or may not function as expected.
Set condition
The vehicle controller detects the LV battery may become overdischarged unless it sleeps, and also determines vehicle conditions are OK to disable LV battery communications.
Clear condition
Clears upon any of the following: (1) The RECONNECT-LV-BATTERY routine is run from the vehicle touchscreen in Service Mode or via Toolbox; (2) A vehicle power cycle is completed; (3) Vehicle firmware install is initiated; (4) The vehicle is no longer in Service Mode.
Signals to check
Open this alert in Service Mode Plus and review the Payload tab. Use the field names below to identify the values shown by your vehicle.
| Signal | Unit |
|---|---|
Lvbmssoc
VCBATT_
|
% |
| Signal | Unit |
|---|---|
Frunk Open
VCBATT_
|
— |
Service Mode
VCBATT_
|
— |
Check other alerts
With Service Mode Plus enabled, open Service Alerts → All. Review the other alerts for clues to the cause of VCBATT_a544.