Open the Frunk and Replace a Dead 12 V Battery

Like any car, a Tesla Model X (2016–2021) has a small 12 V battery that powers the locks, screens and the frunk release — separate from the high-voltage drive battery. When it dies the car won’t wake and the frunk stays shut, and because the Model X has frameless door glass there is one safety step that matters more than on other cars.

Important: before disconnecting the 12 V — or if it has gone flat — lower the driver’s window first if you still can. The frameless doors drop the glass slightly as they open; with no power the glass can’t drop, which risks locking you out and can even shatter the glass if a door is forced.

How to open the frunk when the 12 V battery is dead

1. On the driver’s side of the front bumper, pop off the small tow-hook cover.
2. Behind it are two red pull cords, labelled 1 and 2. Pull cord 1 first, then cord 2 — the frunk releases.
3. If your car instead has jumper terminals there, apply a 12 V jump pack (correct polarity) to pop the frunk. A tiny 9 V battery usually isn’t enough on a Model X.
4. As a fallback, a manual release cable sits in the front wheel-well behind a plastic cover.

How to replace the Model X 12 V battery

1. Open the driver’s door and lower the driver’s window, then power the car off from the touchscreen.
2. The 12 V battery sits in the front, reached after removing the cabin (HEPA) filter housing and apron trim.
3. Disconnect the negative (−) first, then release the red cover and disconnect the positive (+) terminal (about 5 Nm).
4. Fit the correct replacement, reconnect positive first then negative, and refit the trim.

Safety: work only on the small 12 V battery and its wiring — never touch the orange high-voltage cables. From 2022 the Model X moved to a small 16 V lithium low-voltage battery; 2016–2021 cars use a conventional 12 V.

Frequently asked questions

My Model X is dead and I can’t open the frunk or doors — what do I do?
Pop the driver’s-side tow-hook cover off the front bumper and pull the two red cords (1 then 2) to release the frunk, then jump or replace the 12 V battery.

Why lower the window before disconnecting the 12 V?
The frameless door glass drops as the door opens. With no power it can’t drop, so you risk a lockout or shattered glass — dropping the window first avoids it.

Where is the Model X 12 V battery?
In the front of the car, reached behind the cabin-filter housing/apron. It’s the small 12 V battery, not the high-voltage pack.

If a 12 V or electrical warning stays on after the swap, you can look up the fault code on autodtcs.com.