Mercedes-Benz A-Class: lighting & signalling MOT failures
Lighting & signalling was a recorded failure area in 5.1% of Mercedes-Benz A-Class MOT tests in this dataset. It is most prominent on 1999, 2004 cars.
Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair cost: £10–£150 (rough UK ballpark, not a quote).
Lighting & signalling failures by year
| Model year | Tests | Fail rate |
|---|---|---|
| 1999 | 1,635 | 19.0% |
| 2001 | 5,544 | 17.4% |
| 2002 | 8,705 | 18.3% |
| 2003 | 11,674 | 17.2% |
| 2004 | 11,021 | 18.4% |
| 2005 | 23,999 | 14.6% |
| 2006 | 34,980 | 14.0% |
| 2007 | 43,406 | 14.6% |
| 2008 | 46,843 | 12.6% |
| 2009 | 46,758 | 11.9% |
| 2010 | 40,839 | 13.1% |
| 2011 | 34,754 | 11.9% |
| 2012 | 33,415 | 10.6% |
Methodology & source. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.