Tesla Model 3 Tesla Model Y Battery & Low-Voltage DIY possible

Tesla Frunk Won’t Open (Dead 12V): Model 3/Y Fix

By the EV Fix Guide editorial team · Updated October 22, 2026 · How we estimate costs

Quick answer

With a dead low-voltage battery the car will not wake up, and the frunk (where the low-voltage battery is) cannot be opened with the app or key. At a Tesla Service Center this typically costs $100 - $300 (Roadside or Mobile Service visit, if not covered). An independent shop charges about $50 - $150 (Roadside jump service), and doing it yourself costs $40 - $100 (Portable jump starter) — potential savings of 50% - 70%. DIY difficulty: easy (10 - 15 Minutes).

Frunk Won't Open with a Dead 12V Battery (Model 3/Y)

Symptoms

Car does not respond to phone key, key card, or app
Doors will not open from the outside and the screen stays off
Frunk release does nothing, so you cannot reach the low-voltage battery

Repair cost: Tesla vs independent shop vs DIY

Option	Typical cost (USD)
Tesla Service Center	$100 - $300 (Roadside or Mobile Service visit, if not covered)
Independent shop	$50 - $150 (Roadside jump service)
DIY	$40 - $100 (Portable jump starter)
Potential savings	50% - 70%

Ranges are US estimates compiled from owner reports and shop quotes; prices vary by region, model year and parts availability. Report your price.

Can an independent shop fix it?

Roadside assistance, a mobile mechanic, or any shop with a jump pack can open the frunk using the external release wires. Tesla roadside assistance can also help.

Get matched with an independent shop →

How to fix it yourself (easy, 10 - 15 Minutes)

Model 3/Y have two release wires behind the front tow eye cover. Connecting an external 12V power source to them releases the frunk so you can reach the low-voltage battery.

Tools you need

Portable 12V jump starter or another 12V power source with clamps
Plastic trim tool (to pop off the tow eye cover)

Steps

Carefully pop off the tow eye cover on the front bumper (see your owner's manual for where to press or pry).
Pull out the two wires behind the cover.
Connect the red positive (+) clamp of the 12V source to the red wire.
Connect the black negative (-) clamp to the black wire.
The frunk latch releases; open the hood.
Disconnect the 12V source, tuck the wires back in, and refit the cover.
Jump or charge the low-voltage battery following the owner's manual, and replace it if it is failing.

Pro tip: Do not try to drive the car using a jump pack as a long-term fix. A low-voltage battery that went flat once often needs replacing; see our 12V / 16V battery guide.

Had this fixed? Share what you paid

Owner-reported prices keep these ranges honest. We publish only anonymous averages and email you the results.

Frequently asked questions

How much does it cost to fix a frunk that won’t open with a dead 12V battery on a Tesla?

Tesla Service Center: $100 - $300 (Roadside or Mobile Service visit, if not covered). Independent shop: $50 - $150 (Roadside jump service). DIY: $40 - $100 (Portable jump starter). Typical savings versus the service center: 50% - 70%.

Can I fix a frunk that won’t open with a dead 12V battery myself?

Yes. DIY difficulty is easy and it typically takes 10 - 15 Minutes. Model 3/Y have two release wires behind the front tow eye cover. Connecting an external 12V power source to them releases the frunk so you can reach the low-voltage battery.

Can an independent shop fix a frunk that won’t open with a dead 12V battery instead of Tesla?

Yes. Roadside assistance, a mobile mechanic, or any shop with a jump pack can open the frunk using the external release wires. Tesla roadside assistance can also help.

Which Tesla models are affected by a frunk that won’t open with a dead 12V battery?

This issue is reported on the Tesla Model 3 and Model Y.

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Related guides

This guide is for information only. High-voltage components (orange cables) can be lethal — leave them to trained technicians. Not affiliated with Tesla, Inc.