2004 Mercedes-Benz C 1.8L Petrol · SH54 AAX

The most recent MOT tests on this 2004 Mercedes-Benz C reveal a concerning pattern of repeated failures despite identical mileage readings. The vehicle failed twice in December 2025—just eight days apart—before passing on the third attempt on the 30th, all at 144,759 miles. This suggests a persistent underlying issue rather than a one-off oversight, as the same mileage was recorded across multiple tests. The prior cycle in October 2024 similarly ended in a failed test followed by a pass, indicating the problem has persisted for nearly two years. While the absence of recorded defects in any test is unusual—especially for a vehicle of this age—this could imply either a minor, recurring fault that the tester struggled to classify or a deliberate attempt to bypass critical inspections. The most recent pass on 30 December 2025 was just six months ago, meaning the vehicle has not been retested since, leaving a significant gap in verified roadworthiness. The recorded mileage of 144,759 miles over 22 years equates to approximately 6,580 miles annually, which is typical for a vehicle of this age and model. There are no obvious red flags in the mileage progression, as the increments between tests are consistent—around 3,000 miles between the 2023 and 2024 cycles, and another 3,000 miles between the 2024 and 2025 tests. The lack of substantial mileage gaps or rapid accumulation suggests the vehicle has not been left unused for extended periods, which could exacerbate issues like suspension corrosion or drivetrain degradation. However, the repeated failures at identical mileage readings raise suspicion that the problem may not be tied to mileage but rather a mechanical or electrical fault that resurfaced after maintenance or repairs. Given the repeated failures without recorded defects, a buyer should prioritise an independent inspection of the braking system, as binding calipers or worn brake pads are often the most common cause of MOT failures in this class of vehicle. The suspension—particularly the rear bushes and coil springs—should be closely examined for excessive wear or corrosion, as these components frequently fail in vehicles of this age. Additionally, the exhaust system warrants scrutiny for leaks or structural weakness, especially if the vehicle has encountered water damage or been driven in salted conditions. The electrical system, including the ABS and immobiliser, may also require testing, as intermittent faults can lead to repeated MOT failures without clear physical defects. Given the vehicle’s age, corrosion in wheel arches, sills, and the subframe should be assessed, as this is a common silent killer in older Mercedes-Benz models.