Mercedes-Benz S500 L MOT Pass Rate & Official DVSA Failure Statistics

Mercedes-Benz S500 L MOT History and Failure Rates vs UK National Average

The Mercedes-Benz S500 L passed on its first attempt in 89.7%, and its overall record sits +9.6 percentage points above the national average for all cars. These figures come from every recorded DVSA MOT test for the Mercedes-Benz S500 L in the 2023–2025 data: 511 tests across 3 model years (2021–2023). A test still carries exactly one pass or fail verdict.

Figures are computed from every recorded DVSA test for this model in the 2023–2025 data.

Most Common Mercedes-Benz S500 L MOT Problems by Failure Category

Every MOT failure a tester records belongs to one inspection section of the DVSA manual. For the Mercedes-Benz S500 L, the Tyres section leads the record — the breakdown below shows where the recorded failures cluster, then the exact strings behind the three biggest sections.

Shares are over the Mercedes-Benz S500 L's recorded defect strings, merged across its year pages.

Top Recorded Mercedes-Benz S500 L DVSA MOT Test Statistics & Defect Descriptions

The descriptions below are the exact DVSA failure strings testers recorded most often for the Mercedes-Benz S500 L, each with how many of the model's 511 tests it was noted on.

• "Has a bulge, caused by separation or partial failure of its structure" (Major) — noted on about 27 Mercedes-Benz S500 L tests, 5.3% of the model's MOT record.
• "Has a cut in excess of the requirements deep enough to reach the ply or cords" (Major) — noted on about 12 Mercedes-Benz S500 L tests, 2.4% of the model's MOT record.
• "Windscreen damaged but not adversely affecting driver's view" (Minor) — noted on about 10 Mercedes-Benz S500 L tests, 2.0% of the model's MOT record.
• "Has ply or cords exposed" (Major) — noted on about 5 Mercedes-Benz S500 L tests, 1.0% of the model's MOT record.
• "Ball joint excessively worn" (Major) — noted on about 3 Mercedes-Benz S500 L tests, 0.6% of the model's MOT record.
• "Has a lump, caused by separation or partial failure of its structure" (Major) — noted on about 2 Mercedes-Benz S500 L tests, 0.4% of the model's MOT record.

Best and Worst Mercedes-Benz S500 L Model Years by Pass Rate

The strongest Mercedes-Benz S500 L model year on record is 2023 (94.5% across 73 tests), and the weakest is 2021 (89.3%). The gap between them is 5.2 points. Years with fewer than 50 recorded tests are excluded, so these are the years with enough MOT history to mean something.

Mercedes-Benz S500 L reliability is improving in the DVSA data — the pass rate moves about 2.6 points a year across the most recent model years shown above.

Newest model year first. Only years with at least 50 recorded tests are listed.

Pre-MOT Inspection Checklist for Mercedes-Benz S500 L Owners

These checks follow this Mercedes-Benz S500 L's own most-recorded failure strings, starting with what a tester is most likely to flag on a Mercedes-Benz S500 L.

• the windscreen — “windscreen damaged”

  Check the driver’s side of the screen within the swept area for chips and cracks; anything larger than 10mm in the driver’s central view is a fail. Most chips can be resin-repaired for far less than a new screen.

• the suspension joints — “ball joint excessively worn”

  With the car parked on level ground, rock the top of each front wheel in and out while someone watches the suspension arm. Clunks, or rubber boots split and greasy, are what testers record here.

• the lights — “malfunction indicator lamp inoperative or indicates a malfunction”

  Switch everything on and walk round the car: both headlamps on dip and main, every indicator, both brake lights, reverse, fog and the two number-plate lamps. A bulb is a few pounds and a five-minute job.

Derived from the DVSA failure strings testers recorded for the Mercedes-Benz S500 L. A check that finds nothing means the item is likely fine, not that the test is guaranteed.

Frequently Asked Questions: Mercedes-Benz S500 L MOT & Reliability