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Tesla Software Bug Triggers Unexpected Automatic Braking

NHTSA campaign 21V846000 · Reported Oct 29, 2021 · Tesla, Inc.

medium How serious is it? About this label

An unexpected sudden stop increases the risk of a crash. The notice does not tell owners to stop driving.

Key facts

NHTSA campaign number	21V846000
Reported to NHTSA	Oct 29, 2021
Manufacturer	Tesla, Inc.
Part affected	Forward Collision Avoidance: Sensing System: Camera
Vehicles covered	6 model/year combinations, model years 2018–2021
Do-not-drive advisory	No
Park-outside advisory	No
Repair	Free at any franchised dealer; this one can be delivered as an over-the-air software update

What's wrong, in plain English

A communication error in the software running on these Tesla vehicles can trigger a false forward-collision warning or cause the automatic emergency braking system to activate when it isn't needed. If the automatic braking activates unexpectedly, the car can come to a sudden stop while driving. A car that suddenly stops without the driver expecting it raises the chance that another vehicle could crash into it.

What you should do

1. Check your VIN at nhtsa.gov/recalls to confirm your vehicle is included.
2. Your car should receive an over-the-air software update automatically; contact Tesla customer service at 1-877-798-3752 if you have questions.
3. The repair is free.

Where do I find my VIN, and what do I tell the dealer?

Your VIN is the 17-character code on the lower left of the windshield, on your registration and usually on your insurance card. Enter it at nhtsa.gov/recalls to see whether this recall is still open on your car. When you call the dealer, say you have an open safety recall and give them NHTSA campaign number 21V846000. More in how recalls work.

Affected vehicles (6)

2018 Tesla Model 3
2019 Tesla Model 3
2020 Tesla Model 3
2020 Tesla Model Y
2021 Tesla Model 3
2021 Tesla Model S

Who to contact

Tesla — official Tesla recall lookup

Customer service: 1-877-798-3752

Any franchised dealer for the brand can do the repair. Phone numbers are taken from manufacturer sites and recent NHTSA notices; if one has changed, the number in your own recall letter is the one to use.

The bigger picture

Tesla Forward Collision Avoidance Recalls Include Braking and Camera Problems · all 3 Tesla recalls in this area

Other Tesla Model 3 recalls

Aug 5, 2026Tesla Model 3 and Model Y Headlights Too Brighthigh
Jul 7, 2026Model 3 Vehicles Missing Required Safety Featureshigh
May 5, 2026Tesla Model 3, S and Y rearview camera image delayedmedium
Jun 18, 2025Tesla Model 3 and Model Y Seat Fasteners May Be Loosehigh
Feb 14, 2025Tesla Model 3 Power Steering Assist May Failmedium
Jan 7, 2025Tesla Model 3 and Model Y May Lose Backup Camerahigh

All 35 Model 3 recalls

Official notice

Component: FORWARD COLLISION AVOIDANCE: SENSING SYSTEM: CAMERA
Summary: Tesla, Inc. (Tesla) is recalling certain 2017-2021 Model S, Model 3, Model X, and 2020-2021 Model Y vehicles operating software version 2021.36.5.2. A communication error may cause false forward-collision warning (FCW) or unexpected activation of the automatic emergency brake (AEB) system.
Safety risk: Unexpected activation of the AEB system may cause the car to stop suddenly, increasing the risk of a crash.
Remedy: Tesla Service has released an over-the-air (OTA) software update, free of charge. The recall began October 25, 2021. Owners may contact Tesla customer service at 1-877-798-3752. Tesla's number for this recall is SB-21-00-004. (over-the-air software update)

Verify your specific vehicle by VIN at nhtsa.gov. Recall repairs are free of charge by law.