2021 Bmw M340i problems, complaints & recalls
Most-reported problem areas: Engine (7) · Power Train (2) · Suspension (1)
🧭 Reliability snapshot
Compared against other Bmw M340i model years — complaint volume vs the model's median year, recalls and severity. How we score →
Safety recalls (6)
Electrical System:software 2023-08-16 · campaign 23V584000 · 144 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2019-2022 330i, 330i xDrive, M340i, 2022 430i Coupe, 2021-2022 430i, M440i Convertible, and 2020-2022 228i xDrive Gran Coupe vehicles. The receiver audio module control unit software may fail to properly generate audible seat belt warnings to the driver to fasten their seat belt. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."
Risk: An audible chime that does not properly alert the driver to fasten their seat belt increases the risk of injury in a crash.
Fix: Dealers will update the receiver audio module software, free of charge. Owner notification letters were mailed October 12, 2023. Owners may contact BMW customer service at 1-800-525-7417.
Seats 2023-03-29 · campaign 23V211000 · 51 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2019-2021 330i, 330i xDrive, M340i xDrive, 2020-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, 2021 X3 xDrive30e, X4 xDrive30i, and X4M vehicles. The seat frame may not have been welded properly to the seat rails.
Risk: An improperly welded seat frame may not properly restrain the occupant during a crash, increasing the risk of injury.
Fix: Dealers will replace the seat frame and back rest, free of charge. Owner notification letters were mailed May 22, 2023. Owners may contact BMW customer service at 1-800-525-7417.
Seat Belts 2021-07-21 · campaign 21V554000 · 21,537 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2021 2 Series (230i, 230i xDrive, M240i, M240i xDrive), 330e, 330e Xdrive, 4 Series Coupe (430i, 430i xDrive, M440i xDrive) M4 Coupe, M4 Competition Coupe, BMW 4 Series Convertible (430i, M440i), BMW X1 sDrive28i, xDrive28i, 2 Series Gran Coupe (228i, 228i xDrive, M235i xDrive), M2 Competition Coupe, 330i, 330i xDrive, M340i, M340i xDrive, M3, M3 Competition, 530i, 530i xDrive, 540i, 540i xDrive, MINI Hardtop 2 Door (Cooper, CooperS, JCW), X2
Risk: During a crash, a seat belt retractor that does not function as intended increases the risk of injury.
Fix: Dealers will inspect the seat belt retractors (including the seat belts) and, if necessary, replace the retractors, free of charge. Owner notification letters were mailed on September 3, 2021. Owners may contact BMW customer service at 1-800-525-7417; 1-866-825-1525 (MINI); 1-877-877-3735 (Rolls Royce); and 1-888-270-9371 (Toyota).
Seat Belts:front:buckle Assembly 2021-04-28 · campaign 21V298000 · 12 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2021 330i, 330i xDrive, M340i, M3, and 330e xDrive vehicles. The bolt securing the seat belt assembly to the frame was not tightened to specification.
Risk: An improperly installed seat belt assembly may not restrain an occupant as expected, increasing the risk of injury.
Fix: BMW will notify owners, and dealers will inspect the front seat belt buckle assembly connection and, if necessary, replace it, free of charge. Owner notification letters were mailed on June 25, 2021. Owners may contact BMW customer service at 1-800-525-7417.
Back Over Prevention:software 2021-02-19 · campaign 21V096000 · 13,858 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2019-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, X4 xDrive30i, X4 M40i, M550i, X4M, X5 sDrive40i, X5 xDrive40i, X5 xDrive50i, X5M, X5 M50i, X7 xDrive40i, X7 xDrive50i, X7 M50i, Alpina XB7, 330i, 330i xDrive, M340i, M340i xDrive, and 8 Series Coupe, Convertible and Grand Coupe, 840i, 840i xDrive, M850i xDrive, M8, 2020-2021 530e, 530e xDrive, 330e, 330e xDrive, 745Le, 745Le xDrive, X5 xDrive45e, X3 xDrive30e, X6 sDrive40i, X6 xDrive40i, X6 x
Risk: If the driver relies on only the rearview camera image, the missing or reduced rearview image view can increase the risk of a crash or injury.
Fix: BMW will notify owners, and dealers will inspect the rearview camera software and update it if necessary, free of charge. The recall began April 16, 2021. Owners may contact BMW customer service at 1-800-525-7417.
Electrical System:12v/24v/48v Battery 2020-12-09 · campaign 20V761000 · 812 vehicles
Defect: BMW of North America, LLC (BMW) is recalling certain 2021 M340i xDrive, M440i xDrive Coupe, 530i, 530i xDrive, 540i, 540i xDrive, 740Li, 740Li xDrive, 840i Gran Coupe, 840i xDrive Gran Coupe, X5 sDrive40i, X5 xDrive40i, X6 sDrive40i, X6 xDrive40i, and X7 xDrive40i vehicles. The connection between the 48-Volt battery and the starter-generator may not have been assembled properly, which can cause increased electrical resistance at the connections.
Risk: Increased electrical resistance can increase the risk of a fire.
Fix: BMW will notify owners, and dealers will inspect the connection between the 48-Volt battery and the starter-generator assembly, replacing it if necessary, free of charge. The recall is expected to begin April 12, 2021. Owners may contact BMW customer service at 1-800-525-7417.
Service bulletins (183)
Technical service bulletins are repair instructions manufacturers send dealers for known issues. Unlike recalls, the fix is not automatically free — but naming the bulletin at the service desk can save diagnosis time and support goodwill repairs.
Structure:body 2025-04-15 · B010325 · Warranty Program/Extension
the radiator grilles lower active air flap assembly limited warranty for defects in materials and/or workmanship has been extended to 15 years / 150,000 miles as determined from the original first in-service / delivery date.
Electrical System 2025-04-09 · B720225 · Warranty Program/Extension
the supplemental restraint systems (srs) front passenger’s seat occupancy capacitive interior sensor (cis) mat for defects in materials and/or workmanship that causes a false seat occupancy alert to occur has been extended to 10 years / 120,000 miles as determined from the vehicle's original in-serv
Electrical System 2024-01-11 · B611305 · Service Bulletin/Repair Instructions
the electrical system of bmw vehicles has been subject to an ongoing development process over the last few years. this has led to increased demands being placed on the battery. this document covers important information for the dealer on how to handle ã¢ââdischarged batteryã¢ââ complaints.
Service Brakes, Hydraulic 2023-10-13 · B340714 · Service Bulletin/Repair Instructions
functional noises (squealing/honking) when braking shortly before the vehicle comes to a stop. cause material-
Power Train 2023-08-01 · B240323 · Service Bulletin/Repair Instructions
?a software error may cause an unwanted pressure pulsation in the transmission during a "remote engine start."
Exterior Lighting 2023-06-01 · B630821 · Service Bulletin/Repair Instructions
headlight check control (cc) message 128 "high beam headlight failure" is displayed. the following fault codes are stored during a vehicle test: 80419a - left high-beam headlight: short circuit and/or 8041a5 - light outputs: number of permitted short circuit cycles exceeded
Showing the 6 most recent of 183 bulletins. Search all of them free at nhtsa.gov.
What owners report
2026-07-02 · Engine“i have been smelling a burning odor in the vehicle for almost a year which the dealership and an independent shop had not been able to diagnose. the car was recently throwing drivetrain error codes which prompted a visit to the dealership. they found that the 48v battery and negative cable are burnt and quoted $5680 to replace the battery and cable…”
2026-06-29 · Engine“the bmw b58tu oil pump thermoplastic component issue that can cause catastrophic failure to the engine. the the gen 1 oil pump was made from plastic and after issues were discovered, they switched to metal oil pumps. however this known issue is something that bmw has not addressed in the models 2019-2021 that came with the inferior oil pump. …”
2026-05-28 · Engine“i am reporting a safety concern involving bmw vehicles equipped with the b58 technical update (b58tu) engine, commonly found in model years 2019–2021. these vehicles utilize a variable-displacement engine oil pump containing an internal thermoplastic adjusting component responsible for regulating oil pressure. field failures are increasingly being …”
2026-05-18 · Power Train“here’s a strong version that sounds frustrated but still credible and harder to dismiss: i’ve owned many vehicles over the years, and this bmw has been, without question, the most problematic car i’ve ever had. the list of issues has been absurd for a vehicle in this price range and from a brand that markets itself as a premium luxury manufacture…”
2026-05-15 · Engine“i am reporting a safety concern with bmw vehicles equipped with the b58 technical update (b58tu) engine, primarily in 2019–2021 model years. these vehicles use a variable-displacement oil pump containing an internal thermoplastic adjusting component that regulates oil pressure. this plastic part is prone to fracturing, leading to sudden loss or ins…”
2026-03-13 · Engine“ i am reporting a safety concern involving bmw vehicles equipped with the b58 technical update (b58tu) engine, commonly found in model years 2019–2021. these vehicles utilize a variable-displacement engine oil pump containing an internal thermoplastic adjusting component responsible for regulating oil pressure. field failures are increasingly bein…”
2025-10-10 · Suspension“started as low creaking noise coming from front left wheel. slow speeds, over small bumps. over time (one month), creaking noises became louder and more frequent. at that time, steering was starting to feel stiff when turning to the left. taken to 2 bmw dealerships who said it was just a noise and that both tie rods would have to be replaced. upo…”
2025-04-23 · Power Train“while driving through an intersection and making a left turn, a failure of the engine water pump pulley caused the pulley to break apart. this led to damage to the coolant line and tensioner, sudden coolant loss, and the serpentine belt slipping off. the failure occurred mid-turn, causing the vehicle to skid and momentarily lose steering control. …”
2023-11-03 · Engine“at approximately 20,000 miles, vehicle indicated excessively low oil. the dealer indicated oil level was excessively low but did not identify the problem,. the vehicle was filled and returned to owner. within 1000 miles, the incident occurred again. dealer replaced replaced the valve cover claiming that was the issue. now within +/- 1000 miles, …”
Excerpts of consumer complaints filed with NHTSA, lightly truncated. They are owner statements, not verified findings.