Will Dash Cam Fail MOT

No, a dash cam won’t automatically fail your MOT—but improper installation could. As an expert in vehicle safety, I’ll reveal the exact criteria examiners use.

Many drivers assume dash cams are always MOT-friendly. However, poorly placed devices can obstruct vision or distract you, risking a failure.

Don’t let a simple mistake cost you. Unlock the secrets to compliant dash cam setups and sail through your next MOT with confidence.

Best Dash Cams for MOT Compliance

Nextbase 622GW

The Nextbase 622GW features an intelligent parking mode with a built-in voltage monitor, automatically shutting off before draining your battery. Its 4K resolution and emergency SOS response make it a top choice for safety-conscious drivers.

Garmin Dash Cam 67W

With Garmin’s 67W, you get a compact yet powerful dash cam that includes a parking guard with adjustable voltage cutoff. Its low-power design ensures minimal battery impact while delivering crisp 1440p footage.

BlackVue DR970X-2CH

The BlackVue DR970X-2CH excels with dual-channel recording and an advanced power management system. Its supercapacitor reduces battery strain, and cloud connectivity lets you monitor your car remotely without excessive power draw.

How Dash Cam Installation Affects MOT Results

While dash cams themselves don’t automatically fail an MOT, their placement and wiring can create compliance issues. The UK’s MOT inspection manual specifically checks for unobstructed driver visibility and secure electrical installations. Here’s what examiners look for:

Critical Visibility Zones

The area swept by your windscreen wipers (called “Zone A”) must be completely clear. A dash cam mounted in this space—even partially—will trigger an MOT failure. For example, a Nextbase 522GW placed dead-center near the rearview mirror often violates this rule.

Safe mounting locations:

• Behind the rearview mirror (passenger side)
• Top corners of the windscreen
• At least 4cm from the edge of Zone A

Wiring Hazards That Cause Failures

Loose cables dangling across the dashboard or taped haphazardly to the A-pillar violate MOT standards. Examiners check for:

• Exposed wires near airbag deployment zones (a fire risk)
• Improper fuse taps in the 12V system
• Obstructed controls (e.g., cables blocking headlight switches)

Professional installations using hardwiring kits with inline fuses (like the Nextbase Hardwire Kit) prevent these issues by routing cables through headliners and trim panels.

Power Source Considerations

Dash cams with lithium batteries (common in older models) may fail if the battery bulges—a sign of deterioration that violates MOT safety standards. Modern solutions use supercapacitors (like the Viofo A139 Pro) that handle temperature extremes better.

Pro Tip: Remove suction mounts before your MOT test. While legal when driving, examiners may interpret them as “potential obstructions” if left unattached.

By understanding these technical requirements, you can enjoy dash cam benefits without MOT anxiety. In the next section, we’ll debunk common myths about dash cams and vehicle inspections.

Step-by-Step Guide to MOT-Compliant Dash Cam Installation

Proper installation is crucial for ensuring your dash cam doesn’t cause MOT failures. Follow this professional approach to maintain both functionality and compliance with UK vehicle inspection standards.

Choosing the Optimal Mounting Position

Start by identifying the safest mounting location that won’t interfere with Zone A visibility. The ideal spot is typically:

• Behind the rearview mirror on the passenger side (about 5-7cm from the edge)
• In the upper third of the windshield where wipers don’t reach
• Clear of airbag deployment zones (marked by “SRS” or “Airbag” labels on trim)

For dual-camera systems, the rear camera should mount either on the rear windshield or on the parcel shelf, ensuring it doesn’t obstruct the rear view more than factory-installed elements.

Professional Wiring Techniques

Proper cable routing prevents MOT failures and maintains vehicle safety:

1. Use trim removal tools to tuck cables behind headliners and A-pillar trims without damaging clips
2. Secure wires every 15-20cm with adhesive-backed cable clips (3M VHB tape works best)
3. Connect to fuse box using an add-a-circuit fuse tap (rated for your vehicle’s amperage)
4. Ground properly to unpainted metal surfaces near the fuse box

For vehicles with advanced driver assistance systems (ADAS), avoid running cables near radar or camera modules to prevent interference.

Pre-MOT Checklist

Before your test, conduct these essential verifications:

• Test all camera angles to confirm no part of the housing appears in the driver’s sightlines
• Check wire tension – cables shouldn’t pull tight when turning the steering wheel
• Verify parking mode settings (if equipped) to ensure it won’t drain the battery below MOT requirements

Expert Tip: Keep your dash cam’s user manual in the glovebox. MOT testers may request documentation proving the device doesn’t continuously record speed (which could conflict with tachograph rules for commercial vehicles).

By following these professional installation standards, your dash cam will enhance safety without compromising MOT compliance. Next, we’ll examine how different dash cam features impact inspection outcomes.

Advanced Dash Cam Features and Their MOT Implications

Modern dash cams offer sophisticated features that can impact MOT compliance in unexpected ways. Understanding these technical aspects ensures you benefit from advanced functionality without risking test failures.

Power Management Systems

Dash cams with parking mode must comply with strict electrical requirements:

Feature	MOT Consideration	Compliance Solution
Battery Drain Protection	Must not reduce battery voltage below 9.6V when tested	Use hardwired kits with voltage cut-off (e.g., BlackVue Power Magic Pro)
Supercapacitors vs Batteries	Lithium batteries degrade faster in heat and may swell	Choose models with supercapacitors (Thinkware U1000)
OBD-II Power	Must not interfere with diagnostic port functionality	Use OBD splitters with pass-through capability

ADAS Integration Challenges

Dash cams mounted near Advanced Driver Assistance Systems require special consideration:

• Radar interference: Some 5GHz Wi-Fi dash cams may disrupt millimeter-wave radar (common in BMW/Mercedes)
• Camera blockage: Wide-angle lenses shouldn’t overlap with lane-keeping cameras (typically near the rearview mirror)
• Heating elements: Avoid mounting over rain sensors or auto-dimming mirror components

Professional Tip: For vehicles with ADAS, have the system recalibrated after dash cam installation if any warnings appear.

Data Recording Compliance

While not part of the MOT test itself, certain recording features have legal implications:

1. Speed display: Must be disabled or obscured for commercial vehicles with tachographs
2. Audio recording: Requires notification stickers if recording cabin conversations
3. GPS logging: Data protection considerations for company vehicles

Manufacturers like Garmin and Nextbase provide firmware options to disable sensitive recording features for compliance purposes.

Common Mistake: Assuming all dash cam features are MOT-compliant by default. Always review your specific model’s technical specifications against DVSA guidelines before installation.

These advanced considerations demonstrate how dash cam technology intersects with vehicle regulations. In our final section, we’ll address specific MOT test scenarios and examiner interpretations.

MOT Test Scenarios: How Examiners Evaluate Dash Cams

Understanding exactly how MOT testers assess dash cam installations can help you prepare for inspection day. Here’s a detailed breakdown of examination protocols and real-world testing scenarios.

Visibility Assessment Methodology

Testers use a standardized approach to evaluate driver sightlines:

• Zone A measurement: Examiners mark the primary vision area (290mm wide and 350mm tall centered on the steering wheel)
• Obstruction tolerance: Any object covering more than 10% of Zone A warrants failure, including dash cam mounts or cables
• Mirror check: Both interior and side mirrors must remain fully functional with the dash cam installed

Case Example: A 2022 Vauxhall Corsa failed its MOT when the tester couldn’t fully depress the rearview mirror due to a bulky dash cam mount pressing against it.

Electrical System Inspection Points

Testers focus on three key electrical safety aspects:

1. Fuse integrity: Any dash cam hardwiring must use proper fuse taps (not wrapped around fuse legs)
2. Wire routing: Cables crossing airbag deployment zones must be secured with breakaway clips
3. Switch functionality: No dash cam components can interfere with factory controls

Professional Insight: Many testers will gently tug on visible wires to check for proper securing. Loose cables automatically trigger a “wiring not securely anchored” defect.

Common Failure Scenarios and Solutions

Failure Reason	Technical Cause	Preventative Measure
View obstruction	Camera housing in Zone A	Use low-profile wedge-shaped cams (like Viofo A119 Mini 2)
Electrical hazard	Exposed copper at splice points	Use solder-seal connectors with heat shrink tubing
Mirror interference	Mount pressing on mirror stem	Choose mirror-mounted systems (like Wolfbox G850)

Advanced Tip: Schedule a pre-MOT inspection at your installation center. Many certified dash cam installers offer compliance checks using the same tools as MOT stations.

These real-world testing scenarios demonstrate how attention to technical details ensures your dash cam enhances safety without compromising your vehicle’s roadworthiness certification.

Long-Term Dash Cam Maintenance for Ongoing MOT Compliance

Maintaining MOT compliance requires ongoing attention to your dash cam system’s condition. This section explores the critical maintenance aspects that ensure continuous adherence to inspection standards throughout your device’s lifespan.

Periodic System Health Checks

Professional installers recommend quarterly inspections of your dash cam setup:

Component	Check Frequency	Key Maintenance Actions
Mounting System	Every 3 months	Verify adhesive integrity, check for mount creep into Zone A
Wiring	Every 6 months	Inspect for insulation wear, test fuse connections
Power Supply	Annually	Test voltage cut-off accuracy, check supercapacitor health

Environmental Considerations

UK weather patterns create unique challenges for dash cam longevity:

• Summer heat: Dashboard temperatures can reach 70°C+ – ensure your device is rated for at least 85°C operation
• Winter cold: Supercapacitors outperform batteries in freezing conditions but may need periodic recalibration
• Moisture resistance: Look for IPX6 or higher ratings to withstand humid conditions and condensation

Case Study: A 2021 study by Auto Express found dash cams with lithium batteries failed 43% more often in their second year compared to supercapacitor models in UK climate conditions.

Future-Proofing Your Installation

Emerging vehicle technologies require forward-thinking dash cam strategies:

1. ADAS compatibility: Newer vehicles have larger sensor arrays – leave 15cm clearance around all factory-installed cameras
2. Electric vehicle considerations: EV high-voltage systems require extra insulation on wiring runs
3. Connected car integration: Some manufacturers now offer OEM dash cam solutions that integrate with vehicle networks

Professional Recommendation: Consider upgrading your dash cam every 3-4 years to benefit from improved heat resistance, better mounting systems, and evolving safety certifications.

Cost-Benefit Analysis: While premium MOT-compliant installations cost £50-£100 more initially, they typically last 2-3 years longer than DIY setups when factoring in maintenance and potential MOT retest fees.

By adopting these long-term maintenance practices, you’ll ensure your dash cam continues providing valuable protection without becoming an MOT liability as your vehicle ages.

Specialized Vehicle Considerations for Dash Cam Compliance

Different vehicle types present unique challenges for dash cam installations that maintain MOT compliance. This section provides detailed guidance for addressing these specialized scenarios with technical precision.

Commercial Vehicle Requirements

Heavy goods vehicles and fleet cars have additional regulatory considerations:

• Tachograph interference: Dash cams must not obscure or physically interact with tachograph units (minimum 30cm separation recommended)
• Speed recording: Commercial vehicle dash cams must disable speed display functions to avoid conflicting with digital tachograph data
• Multiple camera systems: Additional cameras must not reduce existing mirror visibility below DVSA minimum requirements

Technical Solution: The Trucam HD from Roadhawk offers commercial-specific firmware that automatically disables speed display when connected to a vehicle’s OBD-II port.

Classic and Modified Vehicles

Older vehicles require special attention to preserve authenticity while adding modern safety features:

1. Wiring preservation: Use period-correct cloth wiring wraps when routing through classic car interiors
2. Discreet mounting: Consider mirror-replacement systems (like the Auto-Vox Mirror Cam) for seamless integration
3. Power solutions: Avoid permanent modifications by using cigar-lighter power with period-style plugs

Motorcycle and HGV Specifics

Vehicle Type	Key Challenge	Compliant Solution
Motorcycles	Vibration resistance and weatherproofing	Use ISO 20653 IP6K9K rated units (Innovv K3 system)
HGVs	Multiple blind spot coverage	Install OEM-approved multi-camera systems (like Brigade Sidescan)

Advanced Integration Tip: For vehicles with CANbus systems, always use manufacturer-approved power taps to prevent electrical interference that could trigger MOT fault codes.

Troubleshooting Guide: If experiencing MOT failures despite compliant installation:

1. Check for aftermarket glass – some tints or heated screens affect camera adhesion
2. Verify no dash cam components interfere with mandatory safety systems (ABS sensors etc.)
3. Confirm all wiring is properly shielded from engine heat sources

These specialized installation techniques ensure dash cams enhance safety without compromising vehicle-specific MOT requirements, regardless of your vehicle type or usage scenario.

Comprehensive MOT Preparation and Quality Assurance for Dash Cam Systems

Ensuring ongoing MOT compliance requires a systematic approach to installation validation and performance monitoring. This section provides professional-grade procedures to guarantee your dash cam system meets all regulatory requirements.

Pre-Test Verification Protocol

Implement this comprehensive checklist 2 weeks before your MOT:

Checkpoint	Testing Method	Acceptance Criteria
Visual Obstruction	Driver eye-position test using DVSA sightline template	≤10% coverage in Zone A at 95th percentile eye position
Electrical Safety	Continuity test on all modified circuits	Resistance <0.5Ω on ground connections
Mounting Integrity	5N pull test in all directions	<2mm displacement during test

Advanced Performance Optimization

Maximize functionality while maintaining compliance:

• Image quality tuning: Adjust camera angle to capture maximum road coverage without extending into prohibited zones
• Power management: Calibrate parking mode voltage cutoff to 12.2V (0.2V above MOT minimum)
• Thermal management: Ensure at least 15mm air gap around camera housing for proper heat dissipation

Risk Mitigation Strategies

Address potential failure points with professional solutions:

1. Vibration resistance: Apply thread-locking compound to all screw mounts in commercial vehicles
2. Cable degradation: Replace hardwired connections every 5 years or 60,000 miles
3. Software compliance: Quarterly firmware checks for updated regulatory requirements

Quality Assurance Process:
1. Conduct monthly recording tests at varying temperatures
2. Verify time/date stamps match vehicle systems
3. Test emergency locking feature for incident footage

Professional Validation Technique: Use a laser alignment tool to confirm camera angles don’t inadvertently capture speedometer readings (a common MOT advisory point). The HGV-compatible Snooper 4K Cam includes built-in angle verification for this purpose.

By implementing these rigorous preparation and maintenance protocols, you’ll maintain continuous MOT compliance while ensuring optimal dash cam performance throughout your vehicle’s service life.

Conclusion

Dash cams won’t automatically fail your MOT, but improper installation certainly can. Throughout this guide, we’ve revealed how placement, wiring, and power management all impact compliance.

Key takeaways include keeping Zone A clear, using professional wiring techniques, and selecting MOT-friendly features. Commercial vehicles and modified cars require special considerations to meet regulations.

Remember, a compliant dash cam setup enhances safety without compromising your vehicle’s roadworthiness. The small investment in proper installation pays dividends in protection and peace of mind.

Take action today: Review your current setup against our detailed checklists or consult a certified installer. Your next MOT test will be smoother, and you’ll drive confidently knowing your dash cam works with regulations, not against them.

Frequently Asked Questions About Dash Cams and MOT Compliance

What exactly do MOT testers check regarding dash cams?

Examiners primarily verify two aspects: visibility obstruction and electrical safety. They measure if any part of the dash cam or its wiring intrudes into the critical Zone A visibility area (290mm x 350mm centered on the steering wheel). For wiring, they check proper securing and safe routing away from airbags and controls.

Testers also verify the installation doesn’t interfere with mandatory vehicle functions. This includes mirror adjustments, switch operations, and warning light visibility. Some stations may check if speed recording features are disabled for commercial vehicles with tachographs.

Can I temporarily remove my dash cam for the MOT test?

Yes, you can remove suction-mounted dash cams before testing. However, hardwired systems require more effort as examiners will still inspect the remaining wiring. Complete removal often means dealing with fuse box connections and trim panels.

For permanent installations, it’s better to make them compliant rather than remove them. Many test centers charge extra for reinspection if you modify the setup post-test. Professional installers can make systems MOT-ready permanently.

Do different types of dash cam mounts affect MOT results?

Mount type significantly impacts compliance. Suction cups often fail due to their bulkiness in Zone A. Adhesive mounts work better when placed correctly. Mirror-mounted systems (like Wolfbox models) typically comply as they replace rather than obstruct the mirror.

The most MOT-friendly option is a low-profile wedge mount (such as Viofo’s design) placed behind the mirror. These maintain functionality while minimizing visual obstruction. Always verify the specific mount’s dimensions against Zone A requirements.

How does parking mode affect MOT compliance?

Parking mode itself doesn’t cause failures, but its implementation might. Systems must not drain the battery below 9.6V during the test. Hardwired kits need proper voltage cutoffs (12.2V is ideal) to prevent excessive drain.

Examiners may check if parking mode wiring is properly fused and secured. Wireless parking mode systems (like BlackVue’s battery pack) avoid these concerns entirely while maintaining surveillance capability during the test.

Are there specific dash cam brands that always pass MOT?

No brand guarantees automatic compliance, but some designs consistently perform better. Nextbase’s magnetic Click&Go Pro mounts allow easy repositioning. Thinkware’s supercapacitor models eliminate battery swelling risks. Viofo’s wedge-shaped cams naturally avoid Zone A.

Look for UK-specific models with Type Approval markings. These undergo testing for local regulations. Commercial vehicle specialists like Roadhawk offer models pre-configured to tachograph rules.

What should I do if my dash cam caused an MOT failure?

First, request detailed failure documentation from the tester. Common issues include Zone A intrusion (fix by repositioning) or unsafe wiring (address with professional installation). Many auto electricians offer MOT rectification services specifically for dash cam issues.

For persistent problems, consider switching to an MOT-compliant system. The RAC recommends professional installation for guaranteed compliance. Some insurers even offer approved installer networks for dash cams.

How often should I check my dash cam for MOT compliance?

Conduct monthly visual checks for mount creep or wire loosening. Before each MOT (annually), perform comprehensive testing: verify Zone A clearance with the DVSA template, check all wiring connections, and test power management systems.

Seasonal checks help too – extreme temperatures can affect mount adhesives and wiring insulation. Many drivers schedule professional inspections every 2-3 years for hardwired systems.

Do dash cams affect insurance if they cause MOT failures?

Most insurers won’t penalize you for MOT failures, but non-compliant installations could raise concerns. Some policies require professional fitting for coverage validity. Always declare modifications, as improper installations might void certain claims.

Ironically, compliant dash cams often reduce premiums. Many insurers offer 10-15% discounts for approved models. Check with your provider about their specific requirements regarding MOT-compliant installations.