All Tesla vehicles are equipped with a 354kwh main battery pack that functions as the main source of power. Unlike the main 400V lithium-ion battery that powers the entire electrical system of the Tesla, the vehicle also possesses a separate 12V lead-acid battery that powers peripheral equipment such as the lights, audio system, touchscreen display, etc. This 12V battery, however, is covered by its warranty terms.
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Warranty Length
Tesla, for example, offers a 4 year or 50,000 miles warranty period whichever occurs earlier. However, this warranty doesn't apply to any defect in the product which is caused by abuse, accident, misuse, or improper battery handling. It is a longer warrant factor than nearly all car battery warranties which are generally 2 to 3 years warrant.
What's Covered?
The 12V battery warranty covers the entire or partial failure of the battery, as a result of the inability of charge holding or providing power to the vehicle systems. During the 8-year warranty period, visitors to Tesla service centres who are found to have a faulty 12V battery will be provided a free battery replacement. The cost for the labor problem is also included.
What's Not Covered?
Any damage, such as that caused by neglectful maintenance, accidents or abuse, not the battery 12V warranty and fine print. Apart from these, accelerated loss of battery capacity as a consequence of (but not an outright) failure to use the battery regularly and as intended are not covered in the warranty. The above condition applies only to a spare battery that is replaced under this warranty until the end of the manufacturer's original 4-year unlimited-mileage warranty.
Batteries for 12V will be done under warranty Within Warranty Time
To avoid the possibility of the 12V battery failing, owners are advised to contact the customer support team from Tesla, so Tesla service centre can inspect the car. A technician will test the battery and determined if the battery replacement is included in the warranty coverage. Tesla has developed a unified customer service that can be accessed via the mobile app or the customer service line for service appointments.