2012 Mercedes-Benz C 2.1L Diesel · WO05 AHO

The Mercedes-Benz C-Class in question presents a mixed but deteriorating maintenance profile, with the most recent MOT—conducted just eight months ago in November 2025—revealing a series of persistent and worsening issues despite passing. The November 2025 test at 122,735 miles highlighted critical failures in the previous attempt just three days earlier, including excessive exhaust emissions, a non-functional parking brake (efficiency below 50%), and severe tyre damage on both front tyres, including a side-wall ply separation on the offside. While the vehicle passed on retest, the recurring presence of corroded and contaminated brake pipes—now affecting both front and rear circuits—suggests chronic neglect of fluid system integrity. The missing exhaust silencer and noisy exhaust also indicate long-standing disregard for emissions compliance and drivability, compounded by the fact that these faults have persisted across multiple tests since 2023. The mileage accumulation of 122,735 miles over 14 years aligns with average usage for its age, though the clustering of tests around November each year implies the vehicle may have been driven seasonally or stored for extended periods. The gap between the 2024 and 2025 tests shows a 7,581-mile increase in just 12 months, which is higher than the long-term average and may reflect either intensified use or delayed servicing. Notably, the November 2023 to November 2024 interval saw a 7,482-mile rise, yet the vehicle passed without major failures, suggesting the owner addressed some issues between tests. However, the rapid deterioration in brake and tyre conditions between 2024 and 2025—particularly the parking brake failure and side-wall damage—points to either deferred repairs or worsening mechanical degradation. For a prospective buyer, the most urgent concerns revolve around the brake system, where corroded and grease-contaminated pipes, combined with worn discs and thin pads, signal potential hydraulic failure risks. The distorted front road wheel and damaged tyres demand immediate inspection for alignment issues and hidden wheel damage, as these could lead to uneven wear or sudden failure. The exhaust system’s repeated failures—missing silencer, excessive noise, and emissions—suggest a compromised catalytic converter or exhaust manifold, which may also impact fuel efficiency and emissions compliance. Structural integrity appears less compromised, though the windscreen chip history hints at potential stone-chip damage to other glass surfaces. Finally, the persistent oil leak, though not excessive, warrants closer examination for engine health, particularly if accompanied by blue smoke or reduced performance. Given the vehicle’s age and the pattern of deferred maintenance, a pre-purchase inspection should prioritise a brake fluid flush, pipe condition assessment, and tyre/wheel replacement. The ABS and stability control faults from 2023, though not repeated, may resurface and should be diagnosed via an OBD-II scan. Buyers should also verify whether the exhaust repairs were cosmetic or addressed the root cause of emissions failures, as this directly impacts road tax and MOT passability.