2016 Mercedes-Benz A-Class 1.5L Diesel · GU16 AAX

A recent and serious brake-related failure defines the mechanical risk profile of this 2016 Mercedes-Benz A-Class, with the 2026-02-12 test recording dangerous defects on both rear outer brake pads, which were found to be less than 1.5 mm thick. That same test also failed on parking brake efficiency, a major category defect, before the vehicle was re-presented the following day and passed with advisory items only. The presence of dangerously worn rear pads on a Mercedes rear brake system often points to worn or seized caliper carrier mechanisms, as the inner pad on a floating caliper can sometimes mask the outer pad's condition until the friction material is nearly gone. Given that both rear outer pads were at dangerous levels simultaneously, this is consistent with neglected service intervals rather than isolated pad wear, and a buyer should treat the rear brake system as a priority area for inspection and likely overhaul. The recorded mileage of 114,396 miles over a ten-year life equates to roughly 11,440 miles per year, which sits within typical parameters for a vehicle of this age and is neither unusually low nor disproportionately high. Annual test attendance has been reasonably consistent, with passes recorded in 2023, 2024, and 2025, suggesting the vehicle has been in regular use and on the road through each of those years rather than laid up. That said, the brake wear observed at the 2026 test is notable on a vehicle covering what is, in MOT terms, average annual mileage, and it underlines that wear rates on consumable braking components can accelerate sharply in the final stages of pad life. There is no evidence in the MOT record of mileage irregularity or extended off-road periods, and the only running defect noted across all tests is a persistent tyre pressure monitoring system (TPMS) warning light, present on both the 2026 fail and pass entries. The most recent advisories point clearly to two areas requiring immediate attention. The offside front tyre was recorded at 3 mm tread depth and worn on the edge, which suggests a possible tracking or suspension geometry issue rather than even wear, and a buyer should inspect all four tyres for matching brand, type, and tread depth while also checking the offside front inner and outer edges for feathering. On a test drive, listen for any pulling to one side under braking or acceleration, as uneven front tyre wear is frequently accompanied by a steering drift. The TPMS warning should also be investigated before purchase, as it could simply indicate a faulty sensor or low tyre pressure, but it may also point to a deeper system fault requiring diagnostic scanning with Mercedes-specific equipment. Given the dangerous brake pad readings on the rear axle, a pre-purchase inspection should focus heavily on the rear braking system. Request that the inner rear brake pads be measured directly, as MOT testing only requires the visible outer pad to be checked, and verify that the caliper carriers and slide pins move freely without binding. On a road test, listen for any scraping or grinding noise from the rear wheels, particularly when first applying the brakes from cold, and check for a soft or low-effort parking brake by attempting to hold the vehicle on an incline with the handbrake alone, since the 2026 test flagged parking brake efficiency below requirements. Finally, with the vehicle now approaching ten years of age and over 114,000 miles, the rear brake discs should be inspected for lipping, scored surfaces, and minimum thickness, as replacing pads without addressing worn discs is a false economy.