VCFRONT_a415 — Precharge LV Load Reduction2
Full alert identifier: VCFRONT_a415_prechargeLVLoadReduction2
Alert description
Low Voltage (LV) bus load reduction activated due to inability to precharge the High Voltage (HV) bus. This alert is intended to capture the LV battery conditions when load reduction is activated and assist with diagnosis if primary alert prechargeLVLoadReduction cannot be logged by the vehicle Gateway (GTW) at time of initial occurrence due to LV undervoltage condition.
Potential impact
While this alert is primarily informational and intended for logging purposes, the following LV power feeds are powered off to reduce LV bus load when it sets: Autopilot Electronic Control Unit (ECU), Media Control Unit (MCU), headlight, and sleep bypass.
Set condition
The vehicle controller has detected HV bus precharge as unsuccessful due to low LV Bus voltage, resulting in LV bus load reduction becoming active, and vehicle GTW is reported as available for logging.
Clear condition
Clears automatically after 10 seconds.
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 |
|---|---|
IBS Amp Hours
VCFRONT_
|
Ah |
IBS Current
VCFRONT_
|
A |
IBS Voltage
VCFRONT_
|
V |
LV Battery Temp
VCFRONT_
|
degC |
Dcr Milli Ohms
VCFRONT_
|
mOhms |
| Signal | Unit |
|---|---|
Hv up
VCFRONT_
|
— |
Contactor E Fuse Unstable
VCFRONT_
|
— |
Hv Up Any Trigger
VCFRONT_
|
— |
Hv Up First Trigger
VCFRONT_
|
— |
Hvc E Fuse Unstable
VCFRONT_
|
— |
Pcs E Fuse Unstable
VCFRONT_
|
— |
Vcleft Efuse Unstable
VCFRONT_
|
— |
Vcright Efuse Unstable
VCFRONT_
|
— |
Show 1 more field
| Signal | Unit |
|---|---|
Vehicle Power State
VCFRONT_
|
— |
Check other alerts
With Service Mode Plus enabled, open Service Alerts → All. Review the other alerts for clues to the cause of VCFRONT_a415.