2020 Audi A4 S Line 40 Mhev S-A — MOT failures & pass rate

Across 366 MOT tests analysed for the 2020 Audi A4 S Line 40 Mhev S-A, the most common recorded failure areas were tyres, brakes and lighting & signalling. Its pass rate of 91.8% was above the average for cars of a similar age (90.5%).

Pass rate

366

MOT tests analysed

8.2%

Fail rate

better than

vs cars of similar age

Avg age at test (yrs)

How it compares

Fail rate for this model-year against the segment and national averages for cars of a similar age.

Top failure categories

Most common MOT failure areas — 2020 Audi A4 S Line 40 Mhev S-A
#	Category	% of tests affected	Tests
1	Tyres	5.7%	21
2	Brakes	1.6%	6
3	Lighting & signalling	1.4%	5
4	Suspension	0.8%	3
5	Seat belts & restraints	0.8%	3
6	Emissions & environmental	0.5%	2

Percentage of tests with at least one failure recorded in each category.

Most common specific failures

The exact components most often recorded as failures — more specific than the categories above.

Most frequently recorded failure items — 2020 Audi A4 S Line 40 Mhev S-A
#	Failure item	Times recorded
1	Brake pads	7
2	Tread depth	6
3	Headlamp aim	6
4	Service brake performance	2
5	Size/type	2
6	Tyre pressure monitoring system	1

Top advisory categories

Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.

Most common MOT advisories — 2020 Audi A4 S Line 40 Mhev S-A
#	Category	% of tests with advisory	Tests
1	Tyres	22.9%	84
2	Other defects	9.0%	33
3	Brakes	8.2%	30
4	Suspension	7.1%	26
5	Visibility	2.5%	9
6	Steering	0.3%	1

Failure rate by mileage

Higher-mileage cars tend to fail more — often the most useful guide to real condition.

MOT fail rate by recorded mileage band.

Fail rate by recorded mileage — 2020 A4 S Line 40 Mhev S-A
Mileage band	Tests	Fail rate
0-30k	158	7.0%
30-60k	178	7.9%

Failure rate by age

How this model-year's MOT fail rate climbs as the cars get older.

Trend over time

Fail rate by dataset year — 2020 A4 S Line 40 Mhev S-A
Dataset year	Tests	Fail rate
2023	114	5.3%
2024	124	8.9%
2025	127	10.2%

What to check before buying a 2020 A4 S Line 40 Mhev S-A

Before buying a 2020 Audi A4 S Line 40 Mhev S-A, focus on the areas it most often fails on. Tyres accounted for 5.7% of tests for this year.

Tyres (5.7% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
Brakes (1.6% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
Lighting & signalling (1.4% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.

Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.

Frequently asked questions

How many 2020 Audi A4 S Line 40 Mhev S-As pass their MOT?

91.8% of the 366 2020 Audi A4 S Line 40 Mhev S-A MOT tests in this dataset passed — a 8.2% fail rate.

What is the most common MOT failure on a 2020 Audi A4 S Line 40 Mhev S-A?

Tyres, recorded in 5.7% of tests, followed by brakes (1.6%).

Does the 2020 A4 S Line 40 Mhev S-A get worse with mileage?

Its MOT fail rate rises from 7.0% in the 0-30k band to 7.9% in the 30-60k band.

Methodology & source. Based on 366 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.