You can purchase a new low voltage battery, or dispose of an old one, at a Tesla Service Center.

Perform the following procedure to replace the lead-acid low voltage battery. Wear appropriate personal protection equipment (such as safety glasses, leather gloves when handling the lead-acid battery, etc.).

Removal:

1. Prepare the vehicle to remove the low voltage lead-acid battery:
   1. Ensure the vehicle is in Park.
   2. Lower all windows.
   3. Open the front trunk.
   4. Leave a door propped open so you can get back into the vehicle if needed.
   5. Disconnect the charge cable from the charge port.
2. In the front trunk, remove the vehicle’s underhood apron by inserting a small, non-marring flat tool or your fingers underneath the panel. Pull up to loosen the clips and set the underhood apron aside.

   

3. If equipped, remove the HEPA filter:
   1. Using a 10mm socket, remove the bolt that attaches the washer fluid reservoir neck to the underhood storage unit.

      

   2. Remove the washer tank neck from the vehicle. If the windshield washer reservoir is full, some washer fluid may leak out.
      Note

      You do not need to remove the hose from the neck.

      

   3. With a 10mm socket, remove the bolts (x2) that attach the HEPA filter assembly to the vehicle.

      

   4. Remove the HEPA filter assembly from the vehicle by tilting the rear edge of the filter assembly up past the brake fluid reservoir. Lift the filter assembly out of the vehicle, taking care not to bump into or damage other components.

      

4. Power off the vehicle by navigating to Controls > Safety > Power Off on the touchscreen.
5. With a 10mm socket, loosen the nut that secures the negative (-) terminal clamp to the negative (-) post on the lead-acid battery. Release the terminal clamp from the negative (-) post.

   

6. Disconnect the first responder loop by sliding the red locking tab toward you and pressing the black tab.

   

7. With a 10mm socket, release the terminal cover and loosen the nut that secures the positive (+) terminal clamp to the positive (+) post on the lead-acid battery. Release the terminal clamp from the positive (+) post and cover the terminal clamp with a dry rag.
   CAUTION

   Do not allow the positive (+) terminal clamp to contact nearby components like the lead-acid battery hold down bracket or A/C cooling lines.

   

8. Unplug the vent tube hose from the negative (-) terminal side of the lead-acid battery.

   

9. Loosen the nut on the battery hold down on the top of the lead-acid battery with a 10mm socket. To release the battery hold down, unhook and slide the strap back. If needed, tilt the battery hold down backward so it does not slip into the vehicle.

   

10. Using the battery handle, carefully remove the lead-acid battery, taking care not to touch or damage the surrounding components.
    Warning

    When lifting out the lead-acid battery, stand in front of the vehicle and use proper lifting technique. The lead-acid battery weighs approximately 25 lb (12 kg). Failure to do so may cause serious injury.

    

11. Inspect the new lead-acid battery to ensure it has a red plug in the casing on the positive (+) terminal side. If the new lead-acid battery does not have a red plug, use a small trim tool to transfer the red plug from the old battery to the new one.
    CAUTION

    Dispose of the old low voltage lead-acid battery at a Tesla Service Center, or according to local laws (such as dropping it off at a battery recycling facility). Keep the low voltage battery upright and place it on a towel or piece of cardboard when transporting.

    

Installation:

1. Carefully maneuver the new lead-acid battery into place, taking care not to touch or damage nearby components.
2. Install the lead-acid battery hold down and use a 10mm socket to tighten the nut that secures it to the 12V battery. Torque the nut to 6 Nm (4.4 ft-lb).

   

3. Reconnect the first responder loop.

   

4. Remove the protective caps from the positive (+) and negative (-) posts on the new low voltage lead-acid battery.
5. Connect the positive (+) terminal by positioning the clamp over the positive (+) post. Using a 10mm socket, torque the nut to 6 Nm (4.4 ft-lb).

   

6. Install the positive (+) terminal cover.
7. Connect the negative (-) terminal by positioning the clamp over the negative (-) post. Using a 10mm socket, torque the nut to 6 Nm (4.4 ft-lb).

   

8. Connect the vent tube hose into the negative (-) terminal side of the lead-acid battery.

   

9. Open one of the vehicle’s doors to ensure power has been correctly restored and the touchscreen turns on (this may take several minutes).
10. If equipped, install the HEPA filter:
    1. Carefully maneuver the HEPA fitler assembly into place, taking care not to touch or daramage other components.

       

    2. With a 10mm socket, tighten the bolts (x2) and torque them to 5 Nm (3.7 ft-lb).

       

    3. Ensure the O-ring on the washer tank neck is fully seated, then install the washer tank neck by inserting it into the washer tank.

       

    4. Route the hose so that it is secured by the tab.

       

    5. Use a 10mm socket to install the bolt that attaches the washer fluid reservoir neck to the underhood storage unit. Torque the bolt to 5 Nm (3.7 ft-lb).

       

11. Replace the underhood apron by aligning the clips into their openings in the front trunk. Press down to lock them in place. The clips make an audible clicking sound when secured.

    

12. Close the front trunk. If an alert to replace the low-voltage battery was previously shown on the touchscreen, ensure the alert no longer appears.