Interpret the battery indicator lights while charging
Refer to the image to the left. There is a description written next to each of the green flashing lights that explains the battery charge stages.
NOTE: As the charge progresses, the number of green flashing lights will increase. When the battery is fully charged, all four lights will be illuminated for a brief time and then turn off. All four green LED lights will flash once every five seconds when the battery is charged while still connected to the charger.
Interpret the battery indicator lights when it is discharged
Press the black, circular battery gauge button to view the charge of battery.
Refer to the image above. There is a description written next to each of the green flashing lights that explains the battery charge stages when it is discharged.
How to Interpret V5 Battery Errors
Resolve the error when a red flashing LED is in the fourth position
Charge the battery as soon as possible if the red LED light is flashing five times per second. This indicates that the battery is critically low.
NOTE: If the charger is connected while the LED is flashing, it will continue to flash until the internal voltage has increased above the critical level and the battery is considered stable again.
Correct the error when the flashing LEDs are in the third and fourth positions
Notice the fast flashing red and green LED (for vexos 1.0.3 or later). This indicates an overvoltage error.
Allow the battery to drop below the predetermined threshold, and the error will clear.
Reconnect the battery to the charger to verify that the error has cleared.
Recognize the error when the flashing LEDs are indicative of a bad cell
Understand when the battery shows the red LED with any of the green LEDs briefly flashing (once per second), an internal cell failure has been detected and the battery is essentially dead.
NOTE: This LED pattern indicates that the battery has at least one bad cell. It is advisable to replace the battery.
Understand the error when a red flashing LED is in the fourth position
Disconnect the charger to clear the error if a slow flashing red LED occurs once per second.
Distinguish the fast and slow flashes in the first and fourth positions
Connect the battery to a V5 Brain with valid firmware if the red and green LED are in the first and fourth positions while alternately flashing quickly. This indicates the battery is in firmware bootload mode.
Resolve the error when all LEDs are flashing
Identify if all red and green LEDs are flashing very fast. If this is occurring and the charger is connected, this indicates that the battery is in firmware bootload mode.
Disconnect the charger to allow a firmware update in order to allow all LEDs to turn off, and then connect to the V5 brain.
Resolve the error when no LEDs are lighting up
Connect the battery to the charger and wait an hour before disconnecting.
If the lights do not turn on during the charging process nor light up after the button on the battery has been pressed, use a paperclip or a similarly sized object and press the reset button on the battery shown below.
Connect the battery to the charger once again and wait an hour before disconnecting.
If the issue still persists, the battery is defective and you should email VEX Support at email@example.com.