Top 10 Reasons Cars Fail a Roadworthy Certificate Inspection

Obtaining a roadworthy certificate is an important step when selling, transferring registration, or re-registering a vehicle. A roadworthy inspection helps ensure that a vehicle meets minimum safety standards and is safe to operate on public roads.

Many vehicle owners are surprised when their car fails an inspection, often because of issues that have developed gradually over time. While some problems are minor and easy to fix, others may require professional repairs before a certificate can be issued.

Understanding the most common reasons vehicles fail a roadworthy certificate inspection can help you prepare your car and avoid unexpected delays.

1. Worn or Damaged Tyres
   Tyres are one of the most frequently identified issues during roadworthy inspections. Inspectors check tyre condition, tread depth, and overall suitability for the vehicle.
   
   Common tyre-related reasons for failure include:
   • Insufficient tread depth
   • Uneven tyre wear
   • Cracks or damage to sidewalls
   • Incorrect tyre sizes
   • Exposed cords or structural damage
     
     Worn tyres reduce traction, increase stopping distances, and compromise vehicle safety, especially in wet conditions. Regular tyre inspections can help identify issues before they become roadworthy concerns.
     
     
2. Faulty Brakes
   A vehicle’s braking system is critical for safety, which is why brake-related defects are a leading cause of failed inspections.
   
   Inspectors assess the condition and performance of the braking system, looking for problems such as:
   • Worn brake pads
   • Damaged brake discs or rotors
   • Brake fluid leaks
   • Uneven braking performance
   • Excessive brake wear
     
     If your vehicle pulls to one side when braking, makes grinding noises, or takes longer to stop than usual, it may require brake repair before passing a roadworthy inspection.
     
     
3. Suspension Problems
   The suspension system plays a vital role in vehicle stability, handling, and ride comfort. During a roadworthy inspection, worn or damaged suspension components can result in a failed assessment.
   
   Common suspension issues include:
   • Worn shock absorbers
   • Damaged springs
   • Faulty suspension bushes
   • Excessive movement in suspension components
     
     Signs that you may need suspension repair include excessive bouncing, uneven tyre wear, knocking sounds over bumps, or poor handling. Addressing these issues early can improve both safety and vehicle performance.
     
     
4. Damaged Windscreens and Windows
   Clear visibility is essential for safe driving. Chips, cracks, and other damage that obstruct the driver’s view can cause a vehicle to fail a roadworthy inspection.
   
   Inspectors may identify concerns such as:
   • Cracks within the driver’s field of vision
   • Large chips in the windscreen
   • Poorly repaired glass damage
   • Faulty window operation
     
     Repairing or replacing damaged glass before your inspection can help avoid unnecessary delays.
     
     
5. Faulty Lights and Indicators
   All vehicle lights must operate correctly to ensure visibility and communication with other road users.
   
   Common lighting issues include:
   • Blown headlights
   • Non-functioning brake lights
   • Faulty indicators
   • Damaged lenses
   • Misaligned headlights
     
     Many lighting faults are simple and inexpensive to fix, making them one of the easiest roadworthy failures to prevent.
     
     
6. Steering System Defects
   A safe and responsive steering system is essential for maintaining vehicle control.
   
   Inspectors will examine steering components for signs of wear, looseness, or damage. Common problems include:
   • Excessive steering wheel play
   • Worn steering linkages
   • Leaking power steering components
   • Poor steering response
     
     If your steering feels loose, heavy, or unpredictable, it is advisable to have it inspected by a qualified mechanic before booking a roadworthy inspection.
     
     
7. Worn or Damaged Seatbelts
   Seatbelts are among the most important safety features in any vehicle. Even minor defects can result in a failed inspection.
   
   Inspectors check for:
   • Frayed or damaged webbing
   • Faulty retractors
   • Broken buckles
   • Improper seatbelt operation
     
     Because seatbelts are designed to protect occupants during an accident, they must be in excellent working condition to meet roadworthy requirements.
     
     
8. Fluid Leaks
   Fluid leaks can indicate underlying mechanical issues and may pose safety risks if left unaddressed.
   
   During a roadworthy inspection, leaks involving the following fluids may be identified:
   • Engine oil
   • Brake fluid
   • Power steering fluid
   • Coolant
     
     Regular maintenance and a scheduled car service can help detect leaks early and prevent more serious mechanical problems from developing.
     
     
9. Exhaust System Issues
   The exhaust system must be securely fitted and free from excessive leaks or damage.
   
   Common exhaust-related defects include:
   • Excessive noise
   • Exhaust leaks
   • Loose mounting points
   • Damaged components
     
     A faulty exhaust system can affect vehicle safety, performance, and compliance with roadworthy standards.
     
     
10. Rust and Structural Damage
    Structural integrity is a key focus of any roadworthy inspection. Significant rust or damage can weaken important parts of the vehicle and compromise safety.
    
    Areas commonly inspected include:
    • Chassis components
    • Floor sections
    • Suspension mounting points
    • Structural supports
      
      While cosmetic rust may not always be an issue, extensive corrosion affecting the vehicle’s structure often requires repairs before a Roadworthy Certificate can be issued.

How to Improve Your Chances of Passing a Roadworthy Inspection

Preparing your vehicle before an inspection can save time, money, and frustration.

Some practical steps include:

• Inspecting tyres for wear and damage
• Checking all lights and indicators
• Addressing any brake repair requirements
• Fixing suspension issues promptly
• Repairing visible leaks
• Replacing damaged windscreen glass
• Booking a professional car service

Many vehicle owners choose to have their car inspected by an experienced mechanic before the official roadworthy assessment. A pre-inspection can identify potential problems and allow repairs to be completed beforehand.

Final Thoughts

Failing a roadworthy certificate inspection is often the result of issues that develop gradually through everyday driving. Tyres, brakes, suspension components, lights, steering systems, and fluid leaks are among the most common reasons vehicles do not meet roadworthy standards.

Regular maintenance, prompt repairs, and routine servicing can significantly improve your chances of passing an inspection the first time. By addressing potential safety concerns early, you can keep your vehicle safer, more reliable, and ready for the road.