Tesla MCU1 eMMC Failure Recall: Affected Vehicles, NHTSA 21V-031 & Free Replacement

Background: Why the MCU1 eMMC Wears Out

MCU1 (a Tegra 3 based unit) runs a Linux infotainment stack that writes telemetry, map cache, and logs continuously to an 8 GB eMMC. eMMC has a finite write endurance; after several years of daily use the wear-level reserve exhausts and the chip degrades to read-only or fails entirely. Symptoms include intermittent reboots, slow touchscreen response, "Center Display Reboot Required," loss of backup camera, and ultimately a black screen. NHTSA opened PE20-008 in 2020; Tesla issued recall 21V-031 in early 2021 covering specific Model S (2012-2018) and Model X (2016-2018) builds, expanded over time. The free remedy is an MCU replacement (some VINs received an MCU2 upgrade; most receive a replacement-eMMC MCU1).

Tesla MCU1 eMMC Affected Vehicles

Data sourced from NHTSA recall database (nhtsa.gov/recalls), manufacturer technical service bulletins, and publicly filed class-action documents. Always verify with your VIN before purchase or repair.

How to Check Your VIN for Open Recalls

Recalls are tied to specific VINs, not just model years. Run yours through these free tools before you buy, sell, or schedule a repair:

1. NHTSA VIN Lookup - nhtsa.gov/recalls. Enter your 17-character VIN; shows every open federal safety recall.
2. Manufacturer site - Honda, Toyota, Ford, GM, Hyundai, Kia, Stellantis, Nissan, Tesla, and VW all run their own recall portals. These sometimes list service campaigns, TSBs, and customer support programs that NHTSA does not.
3. Dealer service department - Open recall work is free for the life of the vehicle. No appointment fee, no parts fee.

Use our free VIN decoder to pull build info, or run a free AI diagnosis if you already have symptoms.

Class Actions & Legal References

NHTSA Engineering Analysis EA20-002 and Preliminary Evaluation PE20-008 forced the Tesla recall. Multiple owners pursued small claims actions before the recall was issued; these were largely resolved by the recall remedy.

What To Do If You Are Affected

Check NHTSA.gov/recalls or the Tesla mobile app for an open 21V-031 campaign on your VIN. Do not pay a third-party shop for an MCU repair if the recall is open. Schedule a Tesla service center or Mobile Service appointment.

• Document the symptom at every dealer visit. Same complaint phrasing, video evidence, RO copy in hand.
• Save every receipt - oil changes, towing, rental, prior repairs. Class-action reimbursement requires proof.
• Know your state lemon-law clock. Most states reset the clock with each unresolved repair attempt for the same defect.
• Open a customer-care case with the manufacturer if the dealer cannot resolve the issue. Goodwill assistance is often available out of warranty.

Frequently Asked Questions