High-voltage battery health: what vehicle data means

Check which data is available

Tesla’s manual says your vehicle may not have the Battery Health Test feature. If Battery Health is available under Controls → Service, the screen evaluation uses battery-management-system data and compares energy retention with what is expected for that battery type, age and use. Screen availability and individual features depend on the vehicle and its software.

What the built-in test means

The built-in Battery Health Test is a separate evaluation of energy retention compared with when the battery was new; it is not the same as the kilometre estimate on the display. It can take up to 24 hours, runs while connected to an AC charger supplying at least 5 kW, and requires network connectivity. Before starting, the manual’s listed conditions must be met: the car is in Park, there are no active battery or thermal-system alerts, no software update is pending, and charge is below 20%. Do not deliberately drain the battery to reach this threshold; first check test availability and the on-screen requirements. Tesla recommends running it only when there is concern about energy retention. If the item is absent, that alone is not evidence of a fault. During the test, charge may fall below 10% and even to zero, while climate control and Sentry Mode are disabled. Do not leave people or animals unattended in the car because climate control will be off. Plan for the vehicle to be unavailable for up to 24 hours, and check the on-screen requirements before starting. If you need to unplug during the test, cancel it on the touchscreen first; do not disconnect the vehicle while the test is running.

Why displayed range changes

The distance estimate depends on available energy and the consumption estimate; a cold battery may temporarily show some energy as unavailable. Weather, speed, climate use, route and short trips change consumption, so fewer kilometres on the display cannot be directly converted into a degradation percentage. Compare similar conditions and check whether the display is set to energy percentage or estimated driving range. The Charging screen separates available energy from its estimated distance; a blue part of the battery icon can indicate energy temporarily unavailable because the battery is cold.

When to contact Service

Record any available Battery Health result, alerts and how the change in range affects normal trips. If the estimate or an alert points to an issue, or available capacity materially affects vehicle use, book service through the Tesla app. Do not open the battery or high-voltage components, touch orange cables, or connect test equipment yourself.

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