2021 BMW 120: common problems and what to check
What gets flagged at MOT on 2021 BMW 120s, from 218 tests in 2025, plus known faults and what to look at before you buy one.
Small sample: only 218 of these were MOT tested in 2025, so treat the percentages as rough. The known faults below don't depend on it.
What gets flagged at MOT
The share of 2021 BMW 120 MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.
- Tyres25% of testsRough price £70–£150
At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.
- Brakes8% of testsRough price £150–£350
At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.
- Wipers, windscreen and mirrors4% of testsRough price £15–£250
At the viewing: Check for chips in the driver's view, and test the wipers and washers.
- Lights and electrics3% of testsRough price £10–£80
At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.
- Suspension1% of testsRough price £120–£400
At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.
- Oil and fluid leaks1% of testsRough price £80–£600
At the viewing: Look under the engine and on the ground where the car is usually parked for fresh oil or fluid.
Known faults
Reported by owners, mechanics and buying guides for this model and age. Check which engine the car has, as some apply to one engine only.
- Electrical and warning light faultsAll engines
The main faults reported are electrical: warning lights with no clear cause and infotainment faults.
At the viewing: Test the screen and check no warning lights stay on.
- Particulate filter warnings (diesel)Diesel
Diesels have more problems, including DPF warnings and engine management faults.
At the viewing: Ask what journeys it does, and watch for warning lights.
- Airbag and camshaft recalls (2020)Some cars
Recalls covered the driver's airbag fabric (about 1,100 cars) and camshaft bearing cap screws that could come loose (39 cars).
At the viewing: Ask a BMW dealer to confirm the recalls were done.
Looking at a BMW 120?
Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.
Other years
| Year | MOT tests | Most flagged |
|---|---|---|
| 2022 | 108 | Tyres 21% |
| 2020 | 621 | Tyres 25% |
| 2019 | 642 | Tyres 26% |
| 2018 | 1,396 | Tyres 28% |
| 2017 | 2,316 | Tyres 27% |
| 2016 | 3,349 | Tyres 27% |
| 2015 | 3,584 | Tyres 29% |
| 2014 | 2,942 | Tyres 32% |
| 2013 | 2,330 | Tyres 31% |
| 2012 | 2,386 | Tyres 34% |
| 2011 | 3,160 | Tyres 36% |
| 2010 | 3,451 | Suspension 39% |
| 2009 | 2,909 | Suspension 40% |
| 2008 | 3,328 | Brakes 45% |
| 2007 | 1,964 | Brakes 47% |
| 2006 | 1,752 | Brakes 54% |
| 2005 | 1,712 | Brakes 50% |
| 2004 | 534 | Brakes 47% |
Where this comes from: the DVSA's anonymised results for every MOT test in Great Britain in 2025, counting tests of 2021 BMW 120s registered in 2021. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score