2021 Nissan Sentra: Automatic braking system locks up for no reason
Common wear/failure (not a recall)
Symptoms
Owners of the 2021 Sentra report: automatic braking system locks up for no reason. CarComplaints.com lists 3 owner complaints, average mileage 4,150 miles.
NHTSA has 24 owner complaints for the 2021 Sentra in this area. Examples:
- NHTSA complaint ODI #11768165 (filed 09/30/2026): “I purchased this vehicle brand new in 2021. since then, i have experienced a very concerning safety issue on multiple occasions involving the automatic emergency braking system. while driving normally, with the vehicle operating without any apparent problems,…”
- NHTSA complaint ODI #11714211 (filed 01/29/2026): “Aeb system is initiating emergency braking at random times. both on surface street, and the freeway on ramp. with and without weather, and without any obstacles or cars in the way. the vehicle comes it a complete stop when this happens and puts the driver in…”
Likely causes
Sources do not establish a single root cause; diagnosis is needed. Owner-reported fixes are listed below.
Fix, in plain English
Most common owner-reported solutions on CarComplaints.com: none clearly reported. Check for open recalls and extended warranty coverage with a dealer before paying out of pocket.
DIY difficulty: Moderate
Pads and rotors are a common DIY job with hand tools and a jack; ABS/hydraulic faults need a scan tool. (Our assessment.)
Cost
No sourced cost range: get a written quote after diagnosis.
Typical parts (search links, no affiliate codes)
AutoZone · O'Reilly · Advance · RockAuto
Sources
- CarComplaints.com: Automatic braking system locks up for no reason (2021 Sentra)
- NHTSA complaints API, 2021 Sentra
Page last updated .