Used car guide

2012 Mercedes-Benz CLS petrol: common problems and MOT failures

What MOT testers find on the petrol Mercedes-Benz CLS first registered in 2012 (petrol cars only): we looked at the 349 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.

Small sample: there were only 349 MOTs of these cars during 2023–2025, so treat the percentages as rough. The known faults below don't depend on it.

349MOTs of 2012 petrol cars, done in 2023–2025
80%pass first time (all 2012 cars: 64%)
6,200typical miles a year
2.6×the usual rate for rigid brake pipes

What goes wrong more than usual on a 2012 Mercedes-Benz CLS petrol?

Parts flagged at MOT more often on the 2012 Mercedes-Benz CLS petrol than on all cars registered in 2012.

  • Rigid brake pipes2.6× usual
    Mercedes-Benz CLS
    13.2% All 2012 cars
    5.1%

    Failed outright at MOT: 3.4%, against 0.8% of all 2012 cars. The rest were advisories or minor defects.

    Rough price £100–£400 our estimate

    At the viewing: Ask to see underneath, or check the MOT advisories: corroded brake or fuel pipes get worse every year and fail the MOT when they do.

Better than most

Brake discs: 5.7% here, against 13.8% of all 2012 cars.

Common 2012 Mercedes-Benz CLS petrol MOT failures and advisories

The share of 2012 Mercedes-Benz CLS petrol MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    26% 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.

  • Brakes
    23% 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.

  • Suspension
    10% 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.

  • Lights and electrics
    9% of testsRough price £10–£80

    At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

  • Exhaust and emissions
    3% of testsRough price £100–£1,200

    At the viewing: Look for black soot in the tailpipe, listen for blowing from the exhaust and check for an engine warning light.

  • Wipers, windscreen and mirrors
    2% of testsRough price £15–£250

    At the viewing: Check for chips in the driver's view, and test the wipers and washers.

Questions to ask the seller before buying a 2012 Mercedes-Benz CLS petrol

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

  1. Any recent work on the rigid brake pipes? (Flagged at MOT 2.6× as often on the 2012 Mercedes-Benz CLS petrol as on other cars the same age.)
  2. Can I see the service history and receipts for any big jobs?

Looking at a Mercedes-Benz CLS?

Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.

Other years

Every year of the Mercedes-Benz CLS compared

YearMOT testsMost flagged
2023–Too new for MOT data
2022–Too few tests
2021104Tyres 21%
2020850Tyres 24%
20193,235Tyres 25%
20182,895Tyres 26%
20174,487Tyres 31%
20166,312Tyres 31%
20158,678Tyres 30%
20145,369Brakes 35%
20139,199Brakes 38%
20113,528Brakes 34%
20103,201Brakes 37%
20093,285Brakes 38%
20084,060Brakes 38%
20075,119Brakes 41%
20064,213Brakes 40%
20052,811Brakes 35%

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of Mercedes-Benz CLS cars first registered in 2012. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score