BMW
152,535 MOT tests analysed. sits above the UK fleet average — here's where 520s pass, fail, and end up on the retest sheet.
That's 4.1 points above the UK fleet average across our 1,984 tracked models — a confident result.
Pass
81.6%
Pass-after-fix
3.3%
Fail
14.5%
Avg miles
119,005
Pass + Pass-after-fix + Fail = 100%
Some examples of this model are borderline — a small number of diesels were certified Euro 6 before September 2015. Check your registration on the government's ULEZ checker to be certain. Daily charges if driven in the zone: London £12.50 · Birmingham £8.00 · Bristol £9.00 .
Performance by cohort
2 year bands · 152,474 tests
Pass rate climbs 7.4 points across the cohorts — newer 520 examples clear the test more reliably than the early cars.
Pass
81.5%
Fail
14.5%
PRS
3.4%
Avg mileage at test
119,353 mi
Pass
88.9%
Fail
9.0%
PRS
1.8%
Avg mileage at test
50,820 mi
Cohort = vehicle's first-registration year band. Same model, different generations of build.
The picture
The BMW E12 is the first generation of 5 Series executive cars, which was produced from 1972 to 1981 and replaced the saloon models of the BMW New Class range.
MOT data from 97,218 tests puts this car on a 79.5% first-time pass rate, roughly in line with the UK fleet average. Average mileage at test is 113,789 miles. The most common fail item is tyre tread below the legal limit, followed by cracked or discoloured windscreen.
Buyers weighing up a used 520 should treat the failure breakdown as a pre-purchase checklist. The pass rate is reasonable, but the gap between first attempt and a clean sheet narrows with age and mileage.
ABI Insurance Group
A high-group car — insurance costs will be significantly above average. Lower groups cost less to insure; UK fleet average is around Group 22.
Source: ABI Group Rating Panel · administered by Thatcham Research · groups cover standard variants; performance trims may sit higher. Browse all insurance groups →
32–44
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Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
4,089 occurrences · 2.7% of tests
Tyre tread depth not in accordance with the requirements
3,587 occurrences · 2.4% of tests
A spring or spring component fractured or seriously weakened
2,714 occurrences · 1.8% of tests
A tyre cords visible or damaged
2,193 occurrences · 1.4% of tests
A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
1,877 occurrences · 1.2% of tests
Headlamp reflector or lens slightly defective
1,434 occurrences · 0.9% of tests
A suspension pin, bush or joint excessively worn
1,367 occurrences · 0.9% of tests
A tyre seriously damaged
1,330 occurrences · 0.9% of tests
a brake lining or pad worn below 1.5mm
1,302 occurrences · 0.9% of tests
Wiper blade defective
1,207 occurrences · 0.8% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Worst-case fix budget · top 3 failures
£200–£430
If every one of this 520's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
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Build your own retest budget.
Year-band analysis
First-time MOT pass rate split by registration band. A 7.4-point gap between bands means the year you buy BMW 520 has a real effect on what turns up at the garage.
Best band to buy
88.9%
2018–2020 registration
the 2018–2020 band climbs to 88.9% — a 7.4-point improvement. Tests in this band average 50,820 miles — roughly 69K miles fewer on the clock than the older band. Failures here are mostly wear items: has a cut in excess of the…, tread depth below requirements of 1.6mm — the structural issues that drag down older examples don't appear in the top-10 for this band. The stricter post-2018 MOT test rules meant manufacturers had to tighten up emissions and electrical checks, but this band still shows far fewer major failures on suspension and bodywork than the older fleet.
Band to be cautious about
81.5%
Pre-2018 registration
On the older band (pre-2018), the data shows a 81.5% pass rate against a fleet average of 88.9% on the newer band. The main culprits logged at test: damaged but not adversely affecting driver's view, tread depth below requirements of 1.6mm, and fractured or broken. Average mileage on test for this band is 119,353 miles — high-mileage wear items are a recurring theme.
Best band to buy: 2018-2020 (88.9% first-time pass). Worst band to avoid: pre-2018 (81.5% pass). That's a 7.4-point spread across 151,787 older tests and 687 newer ones — year of build makes a material difference on this model.
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Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a 520 and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.
