When you bring your car in for its annual MOT, it is easy to focus on big items like the brakes, exhaust or engine. But the truth is that minor components such as the horn, the lights and the wipers can quietly become the reason your vehicle fails its test. These faults may look small, but they carry serious consequences – inconvenience, extra cost and even being off the road until fixed. Here’s how to spot the problems ahead of time, and how a dependable local garage can help you avoid a fail.
Why the ‘small stuff’ matters
While tyres, brakes and emissions get a lot of attention, statistics show that a significant share of MOT failures stem from items many motorists overlook. Lighting and signalling alone account for a large number of failures. Issues affecting visibility – such as ineffective wipers or a cracked windscreen – also contribute to the fail rate. The takeaway: even if your vehicle drives fine, these less glamorous components still play a vital role in keeping you safe and legally roadworthy.
Failing an MOT can mean paying for repair work, booking a retest, or even being unable to drive the car until the issue is resolved. A pre-MOT check of these small items offers real value. It is a chance to correct the minor faults before they turn into big hassle.
Horn: easy to ignore, but important to pass
Your horn is a legal safety requirement, yet it is one of the easiest items to neglect. The audible warning device must be loud enough for other road users to hear, and for vehicles first used on or after 1 August 1973 the sound must be continuous or uniform, not harsh or grating. That means novelty horns, multiple-tone horns, gongs or sirens are unacceptable for MOT purposes.
Common faults
- Horn button pressed but no sound, or very weak sound (often wiring, fuse or horn unit issue)
- After-market horns which produce alternating tones or melody-style horn signals
- Horn unit secured poorly, wiring loose or exposed
Pre-MOT check
Find a quiet spot, press the horn and listen: you should hear a clear, steady sound. If it is weak, intermittent or absent, get it checked. Make sure the horn’s mounting is secure and its wiring looks intact. If you’re unsure, bring the car into the garage so we can test and, if required, replace the unit quickly.
Lights: more than just a bulb change
Lighting and electrical faults remain one of the most frequent causes of MOT failure. The test covers front and rear lights, indicators, brake lights, number-plate lamps, hazard lights and, if fitted, fog lights and reversing lamps. Lenses must be undamaged, correctly coloured, securely mounted and aimed properly.
Typical fails
- Blown bulb or one lamp not functioning
- Lens cloudy, cracked or water-filled
- Headlamps misaligned (aim too high, too low or uneven)
- Non-standard colour lights, incorrect positioning or tinted lenses
Pre-MOT checklist
Walk around your car in a low-light environment: turn on dipped beam, full beam, indicators, hazard lights, brake lights, number plate light and reflectors. Check lenses for cracks or moisture. If your headlamps have removable aim adjusters, ensure they look straight. If uncertain, the garage can perform beam alignment for you. A bulb replacement is a cheap fix compared to the cost and hassle of a fail.
Wipers and washers: visibility often overlooked
Poor visibility is a serious safety risk and a common MOT fail area. Conditions affecting the driver’s view include ineffective wipers or a windscreen crack that falls within the swept area. Wiper blades that leave streaks, missed patches or are ineffective in rain will be flagged during the test.
What typically goes wrong
- Wiper blades worn, cracked, rubber missing or hardened
- Washer fluid empty, washer jet blocked or pump not working
- Windscreen damage (chips or cracks) in the wiper’s swept area
- Rear wiper or washer not working correctly on vehicles that have them
Pre-MOT check
Operate the wipers and washers while stationary. Watch the windscreen surface: does the blade leave clean sweeps or are there smears, missed patches or shuddering? Top up the screen-wash reservoir. Inspect the blades for wear and replace them if the rubber looks tired or cracked. At Windmill Garage we can do this quickly and check the washer system for full operation.
Putting it all together: your pre-MOT checklist
Here’s a quick checklist to go through before your MOT:
- Horn: Clear, steady sound. Properly mounted. Wiring intact.
- Lights & signals: All bulbs working. Lenses intact. Headlights aimed correctly. No illegal modifications.
- Wipers & washers: Blades in good condition. No streaking. Washer jets working. Windscreen clean and undamaged in swept area.
Doing this 24 to 48 hours before your MOT gives you enough time to book any quick repairs and avoid a fail. It is a simple step that could save you money and time.
Why choose Windmill Garage for your pre-MOT check & repairs
At Windmill Garage we specialise in pre-MOT inspections that focus not just on the obvious but also on the small but critical faults that often cause fails. Our friendly team explains clearly what needs attention, provides transparent pricing and can fix things like horns, bulbs, wiper blades and washer systems quickly and affordably. By sorting these issues before the test you reduce the risk of failure and enter your MOT with confidence.
Conclusion
Don’t let something as simple as a worn wiper blade, a blown bulb or a silent horn be the reason you fail your MOT. These parts may seem small, but they make a big difference. Spend a little time now checking your horn, lights and wipers or let us handle it with a pre-MOT ch