Auxiliary Battery is Discharged [11/2021 - ]: Description
WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.
General causes of auxiliary battery depletion include the switches of electrical devices mistakenly left on, service life of the auxiliary battery, charging device malfunction, or application of excessive electrical load by the customer, etc.
Therefore, it is important to properly grasp the usage conditions of the customer's vehicle and carry out appropriate troubleshooting (systematized failure diagnosis).
HINT:
If the power is mistakenly left on, the History of Reason for Operation may remain in the certification ECU (smart key ECU assembly).