At a Glance
The Mercedes-benz S-class has 6 identified common problems across 8 generations, with the W126 (1979-1991) being the most affected generation and brakes the most common problem category. Based on 628K MOT tests from DVSA data.
Problems are patterns in the DVSA data that occur significantly more often on a specific model than the UK average — confirmed at 99% statistical confidence. Read our DVSA MOT data methodology →
Below: generation-by-generation comparison of Mercedes-benz S-class common problems, MOT failure types, and pass-rate data drawn from DVSA records. Click any generation to see fuel- and engine-specific fault patterns, mileage-banded repair guidance, and the most common MOT failures testers record.
MOT Tests & Failures by Generation
Mercedes-benz S-class generations by MOT tests, failures, and identified problems from DVSA data
Hover over each bar for a full breakdown. Tap any bar to view that generation's problems.
Showing total MOT tests, failures, and known problems per make. Hover over each bar for a full breakdown.
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Browse Mercedes-benz S-class Generations
Select a generation to see its specific problems, MOT failures and advisories
W108/W109
W116
Most common MOT failure: Brake performance below minimum
W126
Top issue: Spark ignition emissions above threshold
W140
Most common MOT failure: Brake hydraulic component worn
W220
Top issue: Steering lock fault
W221
Top issue: Compression ignition emissions above threshold
W222
Top issue: Rear fog lamp not working
W223
Most common MOT failure: Tyre condition
Most Common Mercedes-benz S-class MOT Failures
Every reason Mercedes-benz S-class vehicles fail their MOT, ranked by frequency. Select an individual year to see only that year’s failures, or stay on ‘All time’ for the combined picture across our 20 years of DVSA data. Scroll inside the table for the full list.
| # | Failure | % of failures |
|---|---|---|
| 1 | Tyre tread depth below limit | 10.99% |
| 2 | Suspension joint or bush worn | 10.15% |
| 3 | Tyre condition | 7.20% |
| 4 | Brake hydraulic component worn | 5.35% |
| 5 | Brake performance below minimum | 4.39% |
| 6 | Wiper blades deteriorated | 4.39% |
| 7 | Windscreen washer not working | 3.50% |
| 8 | Brake pads or linings worn | 3.08% |
| 9 | Headlamp aim defect | 2.99% |
| 10 | Number plate lamp not working | 2.84% |
| 11 | Indicator fault | 2.69% |
| 12 | Exhaust system fault | 2.57% |
| 13 | Front suspension joint worn | 2.38% |
| 14 | Stop lamp not working | 2.03% |
| 15 | Front lamp not working | 1.91% |
| 16 | Track rod end worn | 1.74% |
| 17 | Brake disc or drum worn | 1.54% |
| 18 | Parking brake performance below minimum | 1.49% |
| 19 | Coil spring broken or corroded | 1.48% |
| 20 | Suspension mounting corroded | 1.48% |
| 21 | Rear lamp not working | 1.35% |
| 22 | Rigid brake pipe corroded or damaged | 1.32% |
| 23 | Ball joint dust cover split | 1.32% |
| 24 | Catalytic converter efficiency low | 1.30% |
| 25 | ABS fault | 1.27% |
| 26 | Airbag warning light on | 1.27% |
| 27 | Shock absorber worn or leaking | 1.13% |
| 28 | Headlamp fault | 1.01% |
| 29 | Position lamp not working | 1.01% |
| 30 | Spark ignition emissions above threshold | 0.89% |
| 31 | Windscreen damage affecting view | 0.87% |
| 32 | Exhaust emissions above threshold (non-catalyst) | 0.74% |
| 33 | Fog lamp not working | 0.74% |
| 34 | Body corrosion or damage | 0.74% |
| 35 | Compression ignition emissions above threshold | 0.72% |
| 36 | Mirror damaged or missing | 0.68% |
| 37 | Seat belt condition | 0.66% |
| 38 | Chassis condition | 0.57% |
| 39 | Subframe mounting corroded | 0.54% |
| 40 | Parking brake condition | 0.49% |
| 41 | Horn not working | 0.45% |
| 42 | Front suspension fault | 0.44% |
| 43 | Tyre size or type not matched | 0.34% |
| 44 | Flexible brake hose damaged | 0.28% |
| 45 | Electronic stability control fault | 0.25% |
| 46 | Rear fog lamp not working | 0.24% |
| 47 | Brake pedal fault | 0.22% |
| 48 | Vehicle structure corrosion | 0.22% |
| 49 | Electrical switch fault | 0.22% |
| 50 | Wheel bearing worn | 0.21% |
| 51 | Fuel pipe corroded or damaged | 0.19% |
| 52 | Battery loose or leaking | 0.18% |
| 53 | Dashboard warning lamp fault | 0.18% |
| 54 | Brake pedal movement restricted | 0.17% |
| 55 | Steering rack fault | 0.16% |
| 56 | Steering arm worn | 0.16% |
| 57 | Brake caliper fault | 0.15% |
| 58 | Suspension unit fault | 0.14% |
| 59 | Tyre pressure monitoring system fault | 0.13% |
| 60 | Drag link end worn | 0.13% |
| 61 | Brake fluid leak | 0.12% |
| 62 | Fuel cap damaged or missing | 0.12% |
| 63 | Steering box fault | 0.11% |
| 64 | Steering free play excessive | 0.11% |
| 65 | Suspension arm worn or corroded | 0.11% |
| 66 | Driveshaft fault | 0.10% |
| 67 | Fuel hose damaged or leaking | 0.10% |
| 68 | Electronic parking brake fault | 0.10% |
| 69 | Engine oil leak | 0.09% |
| 70 | Spring mounting corroded | 0.09% |
| 71 | Power steering pipe or hose leaking | 0.09% |
| 72 | Suspension linkage fault | 0.08% |
| 73 | Bonnet catch or hinge fault | 0.08% |
| 74 | Steering damper fault | 0.07% |
| 75 | Steering lock fault | 0.06% |
| 76 | Rear suspension fault | 0.06% |
| 77 | Driver seat fault | 0.06% |
| 78 | Tyre valve stem damaged | 0.05% |
| 79 | Steering operation fault | 0.05% |
| 80 | Brake lever fault | 0.04% |
| 81 | Rear reflector damaged or missing | 0.04% |
| 82 | Power steering pump fault | 0.04% |
| 83 | Propshaft fault | 0.03% |
| 84 | Brake fluid level low or contaminated | 0.03% |
| 85 | Speedometer fault | 0.03% |
| 86 | Electrical wiring fault | 0.03% |
| 87 | Headlamp washer not working | 0.03% |
| 88 | Passenger seat fault | 0.03% |
| 89 | Handbrake cable fault | 0.03% |
| 90 | Headlamp levelling device fault | 0.02% |
| 91 | MacPherson strut worn | 0.02% |
| 92 | Bonded suspension condition | 0.02% |
| 93 | Air suspension levelling valve fault | 0.02% |
| 94 | Bumper damaged or insecure | 0.02% |
| 95 | Rear fog lamp warning light fault | 0.02% |
| 96 | King pin or swivel pin worn | 0.02% |
| 97 | Brake back plate corroded or damaged | 0.02% |
| 98 | Boot lid damaged or insecure | 0.02% |
| 99 | Body security fault | 0.02% |
| 100 | Exhaust leak | 0.02% |
| 101 | Steering intermediate drop arm worn | 0.02% |
| 102 | Electronic braking system fault | 0.02% |
| 103 | Brake fluid warning light on | 0.02% |
| 104 | Anti-roll bar worn or corroded | 0.02% |
| 105 | Driver airbag fault | 0.02% |
| 106 | Fuel tank corroded or leaking | 0.02% |
| 107 | Front passenger door fault | 0.02% |
| 108 | Power steering ram fault | 0.02% |
| 109 | Brake air or vacuum system fault | 0.02% |
| 110 | Transmission oil leak | 0.02% |
| 111 | Brake master cylinder or servo mounting fault | 0.02% |
| 112 | Subframe corrosion or damage | 0.01% |
| 113 | Vehicle floor corroded | 0.01% |
| 114 | Steering column fault | 0.01% |
| 115 | Undertray damaged or missing | 0.01% |
| 116 | Electric power steering fault | 0.01% |
| 117 | Suspension air bellows damaged | 0.01% |
| 118 | Window damaged or won't operate | 0.01% |
| 119 | Steering wheel damaged or insecure | <0.01% |
| 120 | Driver door fault | <0.01% |
| 121 | Handbrake lever fault | <0.01% |
| 122 | Indicator warning light fault | <0.01% |
| 123 | Engine mounting worn or broken | <0.01% |
| 124 | Passenger airbag fault | <0.01% |
| 125 | Brake cable, rod, lever or linkage fault | <0.01% |
| 126 | Trailing arm worn or corroded | <0.01% |
| 127 | Steering coupling worn | <0.01% |
| 128 | Mirror or camera fault | <0.01% |
| 129 | Steering drive system fault | <0.01% |
| 130 | Tie bar or rod worn or corroded | <0.01% |
| 131 | Hydraulic suspension accumulator fault | <0.01% |
| 132 | Handbrake mechanism or mounting fault | <0.01% |
| 133 | Reversing lamp not working | <0.01% |
| 134 | Semaphore indicator fault | <0.01% |
| 135 | Steering shaft fault | <0.01% |
| 136 | Hydraulic brake cylinder fault | <0.01% |
| 137 | Steering lock stop fault | <0.01% |
| 138 | Suspension rod worn or corroded | <0.01% |
| 139 | Hydraulic fluid leak | <0.01% |
| 140 | Main beam warning light fault | <0.01% |
| 141 | Additional braking device fault | <0.01% |
| 142 | Dip switch fault | <0.01% |
| 143 | Exhaust heat shield or sound insulation damaged | <0.01% |
| 144 | Seat belt pre-tensioner fault | <0.01% |
| 145 | Brake fluid reservoir fault | <0.01% |
| 146 | Radius arm worn or corroded | <0.01% |
| 147 | Towbar fault | <0.01% |
| 148 | Stub axle worn | <0.01% |
| 149 | Suspension retaining or locking device fault | <0.01% |
| 150 | Torque or reaction arm worn | <0.01% |
| 151 | Full power hydraulic brake fault | <0.01% |
| 152 | Torsion bar worn or corroded | <0.01% |
| 153 | Body strengthening plate corroded | <0.01% |
| 154 | Brake pressure or vacuum buildup insufficient | <0.01% |
| 155 | Halfshaft fault | <0.01% |
| 156 | Axle corroded or damaged | <0.01% |
| 157 | Brake servo fault | <0.01% |
| 158 | Suspension linkage attachment bracket or mounting corroded | <0.01% |
| 159 | Transmission drive belt fault | <0.01% |
| 160 | Brake valve fault | <0.01% |
| 161 | Brake wheel cylinder fault | <0.01% |
| 162 | Seat belt anchorage fault | <0.01% |
| 163 | Universal joint worn | <0.01% |
| 164 | Speed limiter fault | <0.01% |
| 165 | Brake linkage mounting fault | <0.01% |
| 166 | Front fog lamp not working | <0.01% |
| 167 | Handbrake fails on gradient | <0.01% |
| 168 | Outline marker lamp not working | <0.01% |
| 169 | Tailgate damaged or insecure | <0.01% |
| 170 | Axle beam corroded or cracked | <0.01% |
| 171 | Brake stationary pin worn | <0.01% |
| 172 | Daytime running lamp not working | <0.01% |
| 173 | Hazard warning light fault | <0.01% |
| 174 | Suspension coupling worn | <0.01% |
| 175 | Wheel hub fault | <0.01% |
| 176 | Access panel damaged or insecure | <0.01% |
| 177 | Brake master cylinder fault | <0.01% |
| 178 | Hand-operated brake valve condition | <0.01% |
| 179 | Reversing lamp switch fault | <0.01% |
| 180 | Seat belt or padding damaged | <0.01% |
| 181 | Spare wheel fault | <0.01% |
| 182 | Brake clevis joint worn | <0.01% |
| 183 | Brake slack adjuster fault | <0.01% |
| 184 | CV joint worn | <0.01% |
| 185 | Leaf spring broken or corroded | <0.01% |
| 186 | Leaf spring slipper worn | <0.01% |
| 187 | Load sensing valve fault | <0.01% |
| 188 | Loading door damaged or insecure | <0.01% |
| 189 | Panhard rod worn or corroded | <0.01% |
| 190 | Passenger compartment corrosion | <0.01% |
| 191 | Seat belt load limiter fault | <0.01% |
| 192 | Steering head bearings worn | <0.01% |
Showing all 192 reasons — scroll inside the table for the full list.
Mercedes-benz S-class MOT Failures by Category
Total MOT failure occurrences for the Mercedes-benz S-class, grouped by category. Same data as the failures table above — just sliced by category instead of fault title. Hover a slice for the top failures in each category.
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Frequently Asked Questions
What are the most common Mercedes-benz S-class problems?
Based on analysis of 628K Mercedes-benz S-class MOT tests from DVSA data, we have 6 identified common problems across 8 generations. The most frequently flagged issue is "Compression ignition emissions above threshold". Brakes is the most common problem category.
Which Mercedes-benz S-class generation has the most problems?
The Mercedes-benz S-class W126 (1979-1991) (1979–1991) has the highest number of identified common problems (5). Click the generation card above for the full breakdown.
How is this data calculated?
We analyse anonymised DVSA MOT test records under the Open Government Licence. An issue is classified as a "Common Problem" when it occurs significantly more often on a specific model than the UK average, confirmed at 99% statistical confidence. Read the full methodology page for details.
Can I report a problem with my Mercedes-benz S-class?
Yes — use the "Tell Us About Your Problem" form on this page. Your report helps other Mercedes-benz S-class owners spot problems early. All submissions are reviewed before being added to the public database.
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