Back-up Battery

WARNING: This page is about a different car, the 2018 Buick Regal TourX and 2018 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Do not disconnect the main vehicle battery or remove the telematics fuse with the ignition key in any position other than OFF. Disconnecting power to the telematics communication interface control module in any way while the ignition is ON or with retained accessory power activated may cause activation of the Back-Up Battery. This action is per design as the back-up battery is designed to provide power to the telematics communication interface control module so an emergency notification call can be made after an event where the main battery is disabled or unable to supply sufficient voltage to drive the module. The telematics communication interface control module naturally chooses the main supply voltage as it's default supply. If an emergency call is active, or the network de-registration timer has not expired, and the main supply is removed or lost for any reason the module will use the Back-Up Battery as a power supply to continue the emergency call as long as the default supply can not be detected. If the module is in standby mode and the vehicle battery is disconnected the module will switch to the backup battery for three seconds. If there is no collision event or emergency button press within the three seconds the module will switch off to prevent damage to the backup battery. The back-up battery is not rechargeable and must be replaced if the diagnostics for the DTC (Replace Backup Power Source) indicate it is needed.