Pillar Guide

Understanding MOT Results and Defects: Complete Guide

Comprehensive guide to understanding MOT test results, defect categories, advisories, and certificates. Learn how to interpret your MOT outcome and what actions to take.

Published: December 7, 2025
15 min read

Understanding Your MOT Test Result

Every MOT test concludes with one of two outcomes: pass or fail. However, understanding the detail within these results is crucial for vehicle safety, legal compliance, and making informed decisions about repairs and maintenance.

This comprehensive guide explains everything about MOT results: how to read your certificate, understand defect categories, interpret advisories, and take appropriate action based on your test outcome.

MOT Test Outcomes Explained

Pass Result

A pass means your vehicle met the minimum legal safety and environmental standards at the time of testing. However, a pass can include different scenarios:

Clean Pass:

  • No defects found
  • No advisories noted
  • Vehicle meets all standards fully
  • Best possible outcome

Pass with Minor Defects:

  • Vehicle passed overall
  • Minor defects noted but don't affect immediate safety
  • Should be monitored and addressed
  • Still legal to drive

Pass with Advisories:

  • Vehicle passed overall
  • Items noted that aren't yet defects
  • May deteriorate to become defects
  • Should be monitored for next test

Important: A pass means roadworthy at the time of test. Components can deteriorate afterward. Regular maintenance remains essential.

Fail Result

A fail means dangerous or major defects were found that make the vehicle unsafe or non-compliant.

Fail with Dangerous Defects:

  • Immediate safety risk identified
  • Cannot legally drive except directly to repair garage
  • Requires urgent attention
  • Most serious category

Fail with Major Defects:

  • Significant safety or environmental issues
  • Must be repaired before re-testing
  • Can drive directly to repair garage
  • Legal to drive for repair purposes only

Fail with Multiple Defects:

  • Combination of dangerous and/or major defects
  • All must be addressed before retest
  • Prioritize dangerous defects first

The New MOT Defect Categorization System

Since May 2018, MOT defects are categorized into three levels: Dangerous, Major, and Minor.

Dangerous Defects

Definition: Direct and immediate risk to road safety or serious environmental impact.

Legal Status: Illegal to drive with dangerous defects except directly to pre-arranged repair appointment.

Examples:

  • Brakes: Severely worn pads with less than 1.5mm material, badly corroded brake pipes, brake fluid leaking
  • Tyres: Tread below legal limit (1.6mm), large cuts exposing cords, significant bulges or separation
  • Steering: Excessive play in steering components, broken steering linkage, power steering completely failed
  • Suspension: Broken coil spring, severely damaged shock absorber, suspension arm broken or insecure
  • Structure: Major corrosion affecting load-bearing members, sharp edges from rust near suspension mounts
  • Lighting: Headlight not working on dipped beam, brake lights completely inoperative

Symbol on Certificate: Red triangle with exclamation mark

Required Action:

  1. Do not drive (except to garage)
  2. Arrange immediate repair
  3. Book re-test
  4. Consider recovery if repair not immediate

Driving Restrictions:

  • Only to pre-arranged repair appointment
  • Must take most direct route
  • Vehicle must be insured
  • Consider trailer recovery if multiple dangerous defects

Major Defects

Definition: May affect vehicle safety or have significant environmental impact. Must be repaired.

Legal Status: Must retest after repairs. Can drive directly to repair garage.

Examples:

  • Brakes: Brake efficiency below required standard, damaged brake disc with scoring, seized caliper, corroded brake pipe (not severe)
  • Tyres: Tread approaching limit (below 2mm but above 1.6mm in places), minor cuts or damage, perishing
  • Suspension: Worn shock absorbers, damaged bushes, excessive play in ball joints
  • Steering: Worn track rod ends, power steering fluid leak, excessive play in steering rack
  • Lights: Fog light not working, headlight beam aim significantly wrong, cracked headlight lens
  • Emissions: Emissions above legal limits, catalytic converter missing or obviously defective, DPF removed
  • Corrosion: Rust affecting structural areas but not immediately dangerous, corrosion to chassis

Symbol on Certificate: Amber warning triangle

Required Action:

  1. Get repair quote
  2. Arrange repairs within reasonable time
  3. Book retest (free within 10 working days for eligible items)
  4. Can drive to repair garage by most direct route

Minor Defects

Definition: No significant effect on vehicle safety or environment. Does not cause failure.

Legal Status: Vehicle passes MOT. Should repair soon but not urgent.

Examples:

  • Lights: Number plate light not working, sidelight not working (if multiple fitted)
  • Body: Minor corrosion with no structural impact, small oil leak, washer fluid low
  • Brakes: Slight brake pipe corrosion, brake fluid slightly below maximum
  • Steering: Gaiter slightly damaged but not split, minor play in steering components
  • Suspension: Minor oil leak from shock absorber, slight wear in suspension bush
  • Tyres: Valve cap missing, slight perishing around sidewall

Symbol on Certificate: No symbol or minor notation

Required Action:

  1. Monitor condition
  2. Address during next service
  3. Prevent escalation to major defect
  4. Budget for next test

Timeline: Address before next annual MOT to prevent becoming major defect.

Advisories

Definition: Items that are not yet defects but may deteriorate and require attention in future.

Status: Informational only. Vehicle passes. Not defects.

Examples:

  • Brake pads wearing thin but above minimum
  • Tyre tread reducing but still legal
  • Minor corrosion spots developing
  • Oil leak starting but not significant
  • Exhaust showing early signs of deterioration
  • Slight play developing in suspension components

Symbol on Certificate: Blue information icon

Purpose:

  • Early warning of potential future issues
  • Planning tool for budgeting repairs
  • Maintenance guidance for next service
  • Buyer information when selling vehicle

Required Action:

  1. Note items mentioned
  2. Monitor during year
  3. Consider addressing during service
  4. Budget for next MOT if likely to fail

Important: Advisories don't affect pass status. Ignore at your own risk - they often become defects by next test.

Reading Your MOT Certificate (VT20)

Certificate Information

Vehicle Details Section:

  • Registration number
  • Make and model
  • Colour
  • VIN (Vehicle Identification Number)
  • Test date
  • Expiry date (most important - valid until this date)

Test Details:

  • Test number (unique identifier)
  • Odometer reading at test time
  • Test station name and number
  • Tester name

Defects and Advisories:

  • Any minor defects (if passed)
  • All advisories noted
  • Location codes
  • DVSA manual reference numbers

Understanding Defect Descriptions

Format: Defects use standardized wording from DVSA manual

Location Codes:

  • NS = Near Side (passenger side in UK)
  • OS = Offside (driver's side in UK)
  • F = Front
  • R = Rear
  • Inner/Outer = Specific position

Example: "OS/F Tyre tread depth below requirements (5.2.3e)"

  • Translation: Driver's side front tyre has insufficient tread
  • (5.2.3e) = DVSA manual reference number

Odometer Reading Significance

Recorded Every Test:

  • Creates mileage history
  • Helps detect clocking (mileage fraud)
  • Shows annual usage pattern
  • Valuable for buyers

Mileage Discrepancies: If recorded mileage lower than previous test, certificate shows:

  • "MILEAGE READING IS LESS THAN PREVIOUS READING"
  • Potential fraud indicator
  • Investigate before purchase
  • May indicate replacement instrument cluster (legitimate)

Service History Correlation:

  • Cross-reference with service records
  • Should show logical progression
  • Significant jumps may indicate high usage or odometer issues

Reading Your MOT Failure Notice (VT30)

Failure Certificate Information

Refusal of MOT Certificate Notice:

  • Official title of failure document
  • Lists all defects causing failure
  • Includes any advisories
  • Provides retest information

Defect Categorization: Each defect shows:

  • Category: Dangerous or Major
  • Description: What the problem is
  • Location: Where on vehicle
  • Manual Reference: DVSA manual section
  • Action Required: What must be done

Understanding Reasons for Refusal (RFR)

RFR Codes: Three-digit codes from DVSA manual

Common RFR Categories:

  • 1.x.x: Brakes
  • 2.x.x: Steering and suspension
  • 3.x.x: Visibility (lights, windscreen, mirrors)
  • 4.x.x: Tyres and wheels
  • 5.x.x: Seat belts and seats
  • 6.x.x: Body and structure
  • 7.x.x: Exhaust and emissions
  • 8.x.x: Fuel system

Example RFR: "1.1.11(b)(i) - Brake pad(s) wearing thin (nearside front)"

  • Category 1: Brakes
  • Specific issue: Pads wearing thin
  • Location: Nearside (passenger side) front
  • Severity: Major defect (requires repair)

Retest Information on VT30

Free Retest Eligibility: Notice states whether free partial retest available:

  • Valid if returning within 10 working days
  • Only for specific failure types
  • Must return to same test centre

Excluded Items (full retest fee required):

  • Brake discs or drums replaced
  • Suspension components replaced
  • Welding undertaken
  • Steering components replaced

Partial Retest Items (free if within 10 days):

  • Bulb replacements
  • Wiper blade replacements
  • Horn repairs
  • Minor adjustments

Taking Action After Results

After a Pass

Immediate Actions:

  1. Check expiry date - note in calendar with alerts
  2. Review advisories - plan to address during year
  3. Keep certificate - though digital record is primary
  4. Tax vehicle - if renewal due

Within One Month:

  1. Address minor defects - prevent escalation
  2. Service planning - include advisory items
  3. Budget - for advisory repairs before next test

Throughout the Year:

  1. Monitor advisories - check condition regularly
  2. Maintain vehicle - regular servicing
  3. Pre-MOT planning - book next test early

After a Fail

Immediate Actions (Day of Failure):

  1. Understand defects:

    • Read VT30 carefully
    • Identify dangerous vs major
    • Note all locations

  2. Confirm driving legality:

    • Dangerous defects = no driving (except to garage)
    • Major defects = can drive to repair garage
    • Plan safe route to repair

  3. Get quotes:

    • Test centre quote
    • Independent garage quotes (2-3)
    • Compare prices and parts quality
    • Check reviews

  4. Decide repair location:

    • Test centre (convenient, guaranteed retest)
    • Trusted independent (potentially cheaper)
    • DIY (if capable and simple repairs)

Within 10 Working Days (for free partial retest):

  1. Complete eligible repairs:

    • Simple items first (bulbs, wipers)
    • Return for free retest

  2. Book major repairs:

    • If free retest not possible
    • Don't rush quality for time limit

Beyond 10 Days:

  1. Complete all repairs:

    • Quality over speed
    • Use quality parts
    • Keep receipts

  2. Full retest:

    • Pay full test fee
    • Entire vehicle retested
    • Ensure all defects addressed

Dealing with Dangerous Defects

Safety First:

  • Do not drive except directly to garage
  • Consider recovery options:
    • Mobile mechanic to test centre
    • Trailer recovery
    • Professional vehicle transport
    • Breakdown service (if covered)

Immediate Repair Priority:

  1. Assess urgency
  2. Get emergency quotes
  3. Authorize work quickly
  4. Confirm safety before driving

Common Dangerous Defects and Actions:

Brake Failure:

  • Do not drive
  • Recovery essential
  • Immediate repair critical
  • Check brake fluid levels

Tyre Below Legal Limit:

  • Replace before driving
  • Mobile tyre service available
  • Cannot drive home
  • Check other tyres

Broken Spring:

  • Do not drive (affects handling severely)
  • Recovery needed
  • Both springs on axle may need replacement
  • Check shock absorbers simultaneously

MOT History and Long-Term Records

Digital MOT Records

Database Coverage:

  • All tests from 2005 onwards stored digitally
  • Earlier tests may exist on paper only
  • Accessible free online
  • Permanent historical record

Information Stored:

  • Every test result (pass and fail)
  • All defects found
  • All advisories noted
  • Odometer readings
  • Test dates and locations
  • Test centres and examiners

Checking MOT History

How to Access:

  1. Gov.uk: Official DVSA service at gov.uk/check-mot-history
  2. Free MOT Check: Our service with enhanced readability
  3. Third-party services: Various providers offering additional analysis

Information Needed:

  • Vehicle registration number only
  • Instant results
  • Free access
  • No login required

Using MOT History

For Current Ownership:

  • Pattern Recognition: Identify recurring issues
  • Maintenance Planning: See what fails regularly
  • Budget Planning: Predict upcoming repairs
  • Mileage Verification: Confirm odometer accuracy

For Vehicle Purchase:

  • Mileage Fraud Detection: Check odometer progression
  • Failure History: Identify problematic vehicles
  • Maintenance Quality: See how issues were addressed
  • Recurring Defects: Spot persistent problems

Red Flags in MOT History:

  • Mileage decreasing between tests
  • Repeated failures on same component
  • Long gap in testing (possible SORN or unregistered use)
  • Multiple dangerous defects
  • Advisories never addressed becoming failures

MOT History Analysis

Positive Indicators:

  • Consistent annual testing
  • Clean passes or minor advisories only
  • Advisories addressed in subsequent tests
  • Logical mileage progression
  • Regular maintenance evident

Negative Indicators:

  • Multiple dangerous defects
  • Same issues failing repeatedly
  • Advisories ignored until failure
  • Inconsistent mileage
  • Large gaps in testing

Common Questions About Results

Can I Drive After Failing MOT?

It Depends:

Major Defects Only: Yes, directly to repair garage by most direct route

Dangerous Defects: No, except directly to pre-arranged garage appointment

No Valid Previous MOT: No - current MOT has expired

With Valid Previous MOT: Yes - previous MOT still valid until expiry (even if you failed early test)

Example:

  • Current MOT expires 15 June
  • Test on 20 May and fail
  • Can still drive legally until 15 June on old MOT
  • Must repair defects before old MOT expires

Do Advisories Mean I Failed?

No: Advisories do not cause failure

Pass with Advisories: You passed overall but items were noted

Purpose: Inform you of potential future issues

Action: Monitor and address before next test

Can I Disagree with MOT Result?

Yes - Options:

Immediate Discussion:

  • Speak with test centre manager
  • Ask for detailed explanation
  • View defect in person if possible
  • Request examiner consultation

Formal Appeal:

  • Complaint to test centre
  • Escalate to DVSA if unresolved
  • Request independent inspection
  • Retest at different approved centre

Independent Verification:

  • Get second opinion from trusted mechanic
  • Mobile inspection services
  • Photographic evidence of disputed defect

DVSA Complaint Process:

  1. Complain to test centre first
  2. If unsatisfied, contact DVSA
  3. Provide test details and evidence
  4. DVSA investigates
  5. May result in test centre audit

Successful Appeals Rare: Examiners follow strict standards with little interpretation

How Long Is MOT Certificate Valid?

Standard Period: 12 months from:

  • Test date (if no current MOT), OR
  • Current expiry date (if tested early)

Example 1 (No current MOT):

  • Test date: 5 April 2025
  • Expiry: 4 April 2026

Example 2 (Early test):

  • Current expiry: 20 June 2025
  • Test date: 25 May 2025 (early)
  • New expiry: 20 June 2026 (not 25 May 2026)

Benefits of Early Testing: Can test up to one month (minus a day) early without losing time on certificate

What If I Lose My Certificate?

Not a Problem:

  • MOT records are digital since 2005
  • Paper certificate not required by law
  • DVLA checks digital database automatically
  • Insurance companies can verify online

Replacement:

  • Contact original test centre
  • May charge small fee for reprint
  • Use online checker to view details
  • Keep digital copy/screenshot

Understanding Specific Defect Categories

Brake Defects

Common Issues:

  • Worn pads/shoes
  • Damaged discs/drums
  • Low efficiency
  • Corroded pipes
  • Fluid leaks

Severity Levels:

  • Dangerous: Pads < 1.5mm, badly corroded pipes, significant fluid leak
  • Major: Efficiency below 50%, damaged disc with scoring, minor pipe corrosion
  • Minor: Fluid slightly low, very minor pipe surface rust

Typical Costs:

  • Pads: £40-100 per axle
  • Discs and pads: £80-200 per axle
  • Brake pipes: £60-150
  • Full brake service: £200-400

Tyre Defects

Legal Minimum: 1.6mm tread across central three-quarters

Severity Levels:

  • Dangerous: Below 1.6mm, exposed cords, large bulge
  • Major: Close to limit, significant cuts, perishing
  • Minor: Valve cap missing, slight perishing

Replacement Criteria:

  • Replace at 3mm for safety (not MOT requirement)
  • Any damage should be assessed professionally
  • Bulges require immediate replacement

Costs: £50-150 per tyre (varies by size and brand)

Lighting Defects

Most Common MOT Failure Category: 30% of failures

Typical Issues:

  • Blown bulbs (dangerous if headlight/brake light)
  • Incorrect aim (major)
  • Damaged lenses (major)

Easy Fixes:

  • Replace bulbs yourself (£5-15, 5-10 minutes)
  • Headlight aim requires professional equipment
  • Lens replacement needed for cracks

Emission Defects

Causes:

  • Faulty catalytic converter
  • Lambda sensor failure
  • Engine management issues
  • Poor maintenance
  • Blocked DPF (diesel)

Diagnosis Essential: Emissions failures need professional diagnosis

Costs:

  • Lambda sensor: £80-200
  • Catalytic converter: £200-1,000+
  • DPF cleaning: £80-200
  • DPF replacement: £500-2,000+

Conclusion

Understanding MOT results empowers you to:

Make Informed Decisions: Know what repairs are essential vs advisable

Plan Financially: Budget for repairs based on defect severity

Drive Legally: Understand when you can and cannot drive

Maintain Safety: Address dangerous defects immediately

Preserve Value: Good MOT history maintains resale value

Prevent Issues: Address advisories before they become failures

Key Takeaways:

  • Three defect levels: Dangerous (don't drive), Major (must fix), Minor (monitor)
  • Advisories are warnings, not failures
  • MOT history available digitally from 2005
  • Free partial retest within 10 working days
  • Understanding your results helps prioritize repairs and maintain safety

Check your vehicle's complete MOT history to see all past results, defects, advisories, and mileage progression. Our free service provides instant access to official DVSA records in an easy-to-read format.