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To check a Tesla’s battery energy retention, look for Controls > Service > Battery Health or, on equipped vehicles, run Controls > Service > Battery Health Test. The evaluation uses battery-management-system data; the longer test can take up to 24 hours and requires an AC charger supplying at least 5 kW on the Model 3 and Model Y procedures described in Tesla’s manuals. A displayed-range change by itself does not establish battery degradation.
Choose the right Tesla battery check
Tesla’s built-in options assess energy retention, while the range shown on the touchscreen is an estimate of how far the car may travel. These are related but not interchangeable measures.
| Option | What it tells you | Access and effort |
|---|---|---|
| Battery Health evaluation | An assessment calculated from battery-management-system data and compared with expected energy retention for the battery type, age, and usage. | On covered Model 3 and Model Y vehicles, open Controls > Service > Battery Health. Availability varies by vehicle. |
| Battery Health Test | A longer vehicle-specific assessment that reports energy retention as a percentage compared with when the battery was new. Tesla says the displayed range estimate may be recalibrated afterward. | On equipped vehicles, open Controls > Service > Battery Health Test and follow the prompts. For the cited Model 3 and Model Y instructions, allow up to 24 hours and use an AC charger supplying at least 5 kW. |
| Displayed range | An estimate affected by energy consumption and temperature; it is not, by itself, a direct measurement of battery energy retention. | Visible on the vehicle display. Changes can reflect driving conditions and usage, not only battery aging. |
The cited Model 3 and Model Y manuals say some vehicles may not have the Battery Health Test. Check the owner’s manual for your model year and market, then follow the touchscreen’s instructions. Menu panels can differ by model, year, software, and installed hardware. Tesla release notes say the high-voltage battery state-of-health routine was moved to Controls > Service, so instructions that send every owner into Service Mode may be outdated.
See Tesla’s Model 3 Owner’s Manual, Model Y Owner’s Manual, Service Mode guide, and release notes for vehicle-specific guidance.
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How to run the Battery Health Test
1. Confirm your vehicle supports it
Check the owner’s manual for your exact model year and market, then look under Controls > Service. If Battery Health Test is absent, do not assume that another model’s menu path applies. The manuals’ described feature requires a data connection.
2. Meet the stated prerequisites
For the Model 3 and Model Y procedures cited here, the vehicle should be in Park, have less than 20% charge, have no pending software update or active battery or thermal-system alert, and be connected to an AC charger supplying at least 5 kW. Tesla’s on-screen directions take precedence if the conditions shown for your vehicle differ.
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3. Start the test and leave it undisturbed
Select Controls > Service > Battery Health Test and follow the touchscreen prompts. The cited procedures can take up to 24 hours. The display provides progress information, though the touchscreen may be off during parts of the routine.
- The battery can discharge below 10% and may reach 0%.
- Climate controls and some other features are disabled. Do not leave occupants unattended in the vehicle.
- Heat or loud fan noise may occur during the test.
- Do not use the vehicle or Tesla app, or unplug the charger, while the test is running. If you need to unplug, cancel the test through the vehicle or app first.
Understand the percentage—and its limits
After a completed test, the touchscreen displays a percentage comparing the battery’s energy retention with when it was new. It is an assessment for that vehicle based on battery-management data, not a promise of a specific driving range in every weather or driving condition. Tesla says expected retention depends on battery type, age, and usage, so the percentage should not be treated as a universal pass/fail score or directly compared across different vehicles and battery packs.
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Tesla says the range estimate may be recalibrated after the test. A change in displayed range does not necessarily mean the battery has gained or lost energy; temperature and energy consumption affect range, with cold conditions making the effect more noticeable. Avoid diagnosing degradation from a single range figure.
Tesla recommends using the Battery Health Test when there is concern about high-voltage battery energy retention, rather than running it routinely without a concern. After a completed test, the feature becomes unavailable until the battery-management system detects a change sufficient to measure with another test; it is not an on-demand repeat check.
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When to contact Tesla service
Arrange service if an active battery or thermal alert prevents the test from running, or if the measured energy retention affects the vehicle’s usability. The manuals direct owners to Tesla service in those circumstances. Do not try to work around an alert by forcing the procedure.
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