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When your vehicle fails its MOT, it can be both inconvenient and confusing. At TJ Service, we aim to take the stress out of MOT failures by helping you understand what the problem is and how to fix it quickly.
If your car doesn’t pass the MOT test, you’ll receive a VT30 MOT Refusal Certificate. This document lists the failure reasons and the corresponding MOT failure codes, each tied to a specific part of the vehicle inspection. The data is also stored in the DVSA MOT database, so it’s easy to review later.
Knowing what these codes mean helps you act fast, stay safe, and ensure your vehicle passes its retest.
What Is an MOT Test?
The MOT (Ministry of Transport) test is a legal safety inspection carried out once a year on all vehicles over three years old. It checks essential components such as the brakes, lights, tyres, emissions, and steering to confirm your car meets road safety and environmental standards.
At TJ Service Fleet, we provide DVSA-approved MOT testing for cars, vans, and fleet vehicles. If your vehicle fails, we’ll show you exactly why and provide a clear, fair quote for the necessary repairs. Once fixed, you’ll also benefit from a FREE MOT retest (terms apply).
Not sure when your MOT is due?
Simply enter your vehicle registration on our website to check your MOT expiry date in seconds.
How to Read Your MOT Failure Code
Every MOT failure code points to a specific section of the inspection and gives insight into why your vehicle failed.
For instance, a code like 6.1.b.2 can be broken down as:
- 6 = Section number (Body, Structure, and General Items)
- 1(b) = Component or area inspected
- 2 = Reason for failure
Below is a guide to each main MOT inspection category and what’s covered under each.
1. Lamps, Reflectors and Electrical Equipment
Lighting and electrical problems are among the most frequent MOT failures. The MOT tester checks every light, indicator, and wiring connection to ensure safety and visibility.
Items Checked:
- 1.1 Front, Rear, and Number Plate Lamps
- 1.2 Brake Lights
- 1.3 Rear Fog Lights
- 1.4 Indicators and Hazard Lights
- 1.5 Reflectors
- 1.6 Horn
- 1.7 Headlights
- 1.8 Headlamp Aim
- 1.9 Electrical Wiring and Battery
Quick Tip: A single faulty bulb can cause a fail. Always check all lights before your test.
2. Steering and Suspension
The MOT test ensures that your steering and suspension systems are working correctly and safely. Any damage, play, or corrosion can affect handling and result in a failure.
Items Checked:
- 2.1 Steering Control and Linkages
- 2.2 Steering System and Fluid Leaks
- 2.3 Power Steering Operation
- 2.4 Suspension Components (arms, joints, and mountings)
- 2.5 Front Suspension and Bearings
- 2.6 Rear Suspension
- 2.7 Shock Absorbers
Tip: If your vehicle drifts, knocks, or feels unstable, have it checked before your MOT.
3. Brakes
Your braking system must perform efficiently and evenly across all wheels. During the MOT, testers measure braking power and balance to ensure safety.
Items Checked:
- 3.1 Parking Brake and Controls
- 3.2 Hydraulic, Air, or Vacuum Brakes
- 3.3 ABS and Stability Control Systems
- 3.4 Brake Pads, Discs, and Calipers
- 3.5 Pipes, Hoses, and Valves
- 3.6 Brake Performance and Efficiency
Safety Note: Brake pads under 1.5mm thick will fail your MOT. Replace them at 3mm to stay road-safe.
4. Tyres and Road Wheels
Tyres must be safe, roadworthy, and correctly fitted. The tester checks for tread depth, wear, and damage.
Items Checked:
- 4.1 Tyres: Type, Size, Load Rating, and Tread Depth
- 4.2 Wheels: Fixing, Condition, and Security
Legal Requirement: Tyre tread depth must be at least 1.6mm across the middle 75% of the tyre.
At TJ Service, we stock premium, mid-range, and budget tyres, with same-day fitting available.
5. Seat Belts and Supplementary Restraint Systems (SRS)
Seat belts and airbags are critical safety components. The MOT test checks they’re properly fitted, secure, and functional.
Items Checked:
- 5.1 Seat Belt Requirements
- 5.2 Seat Belt Condition
- 5.3 Installation and Anchorage
- 5.4 Airbags and Restraint Systems
Tip: Make sure all belts click, retract, and lock correctly. An illuminated airbag light will cause an automatic fail.
6. Body, Structure and General Items
Your car’s structure must be free from dangerous rust or damage. The MOT inspector checks that all panels, doors, seats, and fixings are secure.
Items Checked:
- 6.1 Vehicle Structure and Mountings
- 6.2 Seats and Doors
- 6.3 Registration Plates and VIN
- 6.4 Load Security
- 6.5 Speed Limiter (if fitted)
- 6.6 Towbars
- 6.7 Driving Controls
We offer rust repairs, welding, and underbody protection to help you pass your MOT confidently.
7. Exhaust, Fuel and Emissions
Your vehicle’s exhaust and fuel systems must be secure, leak-free, and meet emissions standards.
Items Checked:
- 7.1 Exhaust System
- 7.2 Fuel System
- 7.3 Petrol Emissions (CAT and BET Tests)
- 7.4 Diesel Emissions (Smoke Test)
If your car fails the emissions test, it may need DPF cleaning, catalytic converter repair, or sensor replacement.
8. Driver’s View of the Road
Visibility is key for safe driving. Testers check that your windscreen, mirrors, and wipers provide a clear, unobstructed view.
Items Checked:
- 8.1 Mirrors and Rear View
- 8.2 Wipers and Washers
- 8.3 Windscreen Condition and Damage
- 8.4 Bonnet Security
Tip: Chips or cracks over 10mm in the driver’s field of vision will fail.
Prevent MOT Failure with TJ Service
At TJ Service, we don’t just test your vehicle, we help you pass confidently. From pre-MOT checks to complete repairs, our qualified technicians ensure your car meets DVSA standards every time.
- DVSA-Approved MOT Testing Centre
- Free Retests (Terms Apply)
- Straightforward, Honest Pricing
- Professional Repairs for All Vehicle Types
- Fleet MOT Testing Available
Don’t let an MOT failure slow you down.
Call TJ Service in Fleet today or book your MOT online to keep your vehicle safe, legal, and road-ready.
