AI Damage2021 Subaru Legacy: common problems
Owners of the 2021 Subaru Legacy filed 31 complaints with NHTSA, most often about air bags and visibility. The maker issued 450 service bulletins for this year. Details by component below, with sources.
Key figures
- Owner complaints
- 31
- Technical service bulletins (TSB)
- 450
What fails most often
- 1 Air bags 19% of all complaints
- 2 Visibility 19% of all complaints
- 3 Electrical system 16% of all complaints
- 4 Powertrain 6% of all complaints
- 5 Engine 6% of all complaints
- 6 Service brakes 6% of all complaints
- 7 Forward collision avoidance 6% of all complaints
- 8 Backover prevention 6% of all complaints
- Air bags: 6 complaints (19% of all); manufacturer bulletins for this component: 19.
- Visibility: 6 complaints (19% of all); manufacturer bulletins for this component: 9.
- Electrical system: 5 complaints (16% of all); manufacturer bulletins for this component: 273.
- Powertrain: 2 complaints (6% of all); manufacturer bulletins for this component: 56.
- Engine: 2 complaints (6% of all); manufacturer bulletins for this component: 52.
Engines and transmissions
US-market versions per EPA. On the right: how many NHTSA complaints name this engine or transmission type.
- 2.4 L · petrol · turbo · 4 cyl
- 2.5 L · petrol · 4 cyl
- CVTnamed in 1 complaints
Drive: AWD
Symptoms owners describe
How many of the 31 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Air bags | 6 | 0 | 19 |
| Visibility | 6 | 0 | 9 |
| Electrical system | 5 | 0 | 273 |
| Powertrain | 2 | 0 | 56 |
| Engine | 2 | 0 | 52 |
| Service brakes | 2 | 0 | 4 |
| Forward collision avoidance | 2 | 0 | 3 |
| Backover prevention | 2 | 0 | 0 |
| Equipment | 1 | 0 | 131 |
| Engine and cooling | 1 | 0 | 48 |
| Seats | 1 | 0 | 24 |
| Structure | 1 | 0 | 11 |
| Suspension | 1 | 0 | 6 |
| Seat belts | 1 | 0 | 1 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
Vehicle: 2021 Subaru Legacy Base 2.5i Mileage:~65,000 miles My engine suddenly began making loud internal knocking/tapping noises with no warning lights, no overheating, and no prior symptoms. The vehicle immediately became unsafe to operate.
Car intermittently will studder and not go into first gear or go into second gear dangerously having car bog down and almost stall and then it violently downshifts having car RMP Hague go very high then slip and have no power to wheels and then a few seconds later go into second gear violently taking off again.
The contact stated that while driving at various speeds during colder weather, the heater failed to operate as intended. Additionally, the Eyesight system was inoperable. The check engine and other unknown warning lights were displayed.
CVT Transmission Failure. Failure occurred at approximately 66,706 miles on 5/16/25. The Check Engine and AT Temp lights appeared in the instrument cluster. The driving conditions when this happened were a safety concern.
Subaru has released a service bulletin regarding concerns with the Thermo Control Valve in specific vehicles. Unfortunately, individuals with vehicles bearing a rebuilt title, including myself, are required to cover expenses exceeding $2,000 out of their own pockets.
The contact received notification of NHTSA Campaign Number: 24V227000 (AIR BAGS); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue.
A Recall was issued Mar 22, 2024 for a dangerous safety issue. AN AIR BAG That Does NOT Deploy During A Crash CAN Increase THE Risk OF Injury. Remedy Dealers Will Replace THE ODS Sensors ON THE Front Passenger Seat, Free OF Charge. Interim Letters Informing Owners OF THE Safety Risk Were Mailed MAY 17, 2024.
ODS sensor recall still not fixed/remedy available, used heat for first time since i purchased the car, minor cracks in the windshield, car radio/monitors randomly go black, reverse camera won’t work, restarts on there own after a while
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 1,072 of 2,102 model years in the NHTSA data (among the 49% least complained about).
On average one model year of the Legacy has 73 complaints (10 years in the data). This year has 31, below average.
What to check before buying
- Air bags. Check the SRS light, stored codes and airbag/curtain status after any impact.
- Visibility. Wipers, mirrors, defrosters, cracked glass.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
Manufacturer service bulletins
Bulletin titles as filed with NHTSA.
- This announcement provides information on a new software update for the Midtronics Dss and DCA machines
- This announcement provides information on an enhancement of the TechShare CVT diagnostic assitance application
- This bulletin provides paint code information for 2027 model year vehicles
- "This Bulletin announces additional troubleshooting steps for the following DTCs
DTC C1956: RH Actuator Circuit DTC C1957: LH Actuator Circuit"
- This announcement provides an update to all 2027 model year Subaru warranty coverages for wear items and…
- This bulletin contains illustrations of exchange components and their manufacturer as well as a…
This bulletin contains illustrations of exchange components and their manufacturer as well as a description of the proper exchange procedure. This is an revised version of the original bulletin.
- In the interest of customer satisfaction, Subaru of America, Inc
(SOA) is extending the New Car Limited Warranty coverage for the CP1 & Gen 3.1 Head Unit used in the listed models and model years to (8) eight years / 150,000 miles to cover certain qualifying repairs to the…
- This bulletin has been developed to outline the steps for gathering basic but essential information during…
This bulletin has been developed to outline the steps for gathering basic but essential information during diagnosis of Infotainment concerns. This is an revised version of the original bulletin.
- This bulletin announces reprogramming file availability and provides a software update installation…
This bulletin announces reprogramming file availability and provides a software update installation procedure to optimize the new Gen 4 Denso CP1 Audio and Navigation head units utilized in the models listed.This is an…
- This bulletin provides a procedure to address customer concerns of surface rust accumulating in the top…
This bulletin provides a procedure to address customer concerns of surface rust accumulating in the top center retaining nut area of the front strut mounts. This is an revised version of the original bulletin.
- This bulletin provides guidance when diagnosing chain slip, judder, shudder, and hesitation concerns on…
This bulletin provides guidance when diagnosing chain slip, judder, shudder, and hesitation concerns on the TR580 model CVT transmissions used in the models listed.
- This service bulletin outlines the diagnostic and repair procedure for white smoke emitted from the…
This service bulletin outlines the diagnostic and repair procedure for white smoke emitted from the exhaust after startup. This is an revised version of the original bulletin.
NHTSA lists 450 bulletins for this year; the 12 newest are shown here.
Other years of this model
Questions and answers
What are the most common problems with the 2021 Subaru Legacy?
Owner complaints to NHTSA most often mention: air bags, visibility, electrical system. Total complaints: 31. The most frequent symptoms in complaint texts: warning lights, check engine (29%), infotainment or screen glitches (13%), stalls while driving (13%).
How many service bulletins (TSB) were issued for the 2021 Subaru Legacy?
NHTSA lists 450 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2021 Subaru Legacy from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2021 models
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-04.