Lexus Rx450h MOT Failures
An analysis of 13,057 real DVSA MOT tests on the Lexus Rx450h — what fails, how often, and how that compares to every other car on UK roads. Generations covered: AL10 (2009–2015), AL20 (2015–2022).
Where the Lexus Rx450h fails its MOT
The single biggest MOT failure point on the Lexus Rx450h is light unit fault — this model is 8.3 times more likely to fail on this item than the average car on UK roads. That makes it worth watching for anyone buying or owning this model. Across 13,057 MOT tests, 1.86% of all Lexus Rx450h tests recorded this as a failure.
Lighting faults are usually straightforward to fix (bulbs, connectors, earth points) but can indicate deeper wiring issues on older cars. Check all lights including fog lamps, number plate lights, and dashboard warning lights.
Other notable weak points include front or rear fog lamp not securely attached (20x the fleet average), suspension joint dust cover severely deteriorated (10x the fleet average), and suspension pin, bush or joint worn (5.9x the fleet average). These ratios compare the Lexus Rx450h's failure rate on each item against the national average for all cars tested — a ratio of 10x means this model fails ten times more often than a typical car.
The failures span 2 categories: Lights & Electrics, Suspension. If you're inspecting a Lexus Rx450h before purchase, these are the areas to focus on — and if any have been flagged as advisories on a previous MOT, they're likely to become failures in the near future.
How failures change with mileage
The Lexus Rx450h's weak points shift as the car covers more miles. Understanding these patterns helps you know what to expect — and what to budget for — at each stage of ownership.
Under 60,000 miles
At this mileage, most failures are either design-related or caused by age rather than wear. Components like bushes and drop links may not have been replaced yet, and original-fit parts can deteriorate even on low-mileage cars that spend a lot of time sitting.
The standout failure at this mileage is suspension pin, bush or joint worn at 5.9x the fleet average.
60,000 to 100,000 miles
This is where routine wear items start to show up. Brake components, tyres, and exhaust parts have done serious work by this point. Cars that have been well serviced will show fewer of these failures — this mileage band is where good maintenance really separates the well-kept from the neglected.
For the Lexus Rx450h specifically, the DVSA data shows the most common failures at this mileage are front or rear fog lamp not securely attached (20x the average) and suspension joint dust cover severely deteriorated (10x). light unit fault (8.3x) and light unit fault also appear frequently.
Over 100,000 miles
High-mileage cars accumulate failures across multiple systems. The key question isn't whether things will need doing — they will — but whether the car has been maintained well enough to keep on top of them. Look for a consistent service history and recent MOT passes with minimal advisories.
The standout failure at this mileage is light unit fault at 5.0x the fleet average.
The shift from suspension pin, bush or joint worn at lower mileages to light unit fault at higher mileages is typical — early failures tend to be design or factory-related, while high-mileage failures reflect accumulated mechanical wear. A car that's been well maintained will usually dodge the worst of both.
Known issues beyond the MOT
An MOT only tests roadworthiness at a single point in time — it won't catch developing faults, intermittent problems, or issues that haven't yet reached the failure threshold. These are the issues that Lexus Rx450h specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.
Brake system warning lights and ABS issues (AL10/AL20) Major
NHTSA complaints document multiple cases of ABS, brake, traction control and VSC warning lights illuminating simultaneously, often accompanied by a hard brake pedal and audible warning chimes. Affects AL10, AL20; typical independent garage repair cost is £200–£600.
Suspension bush and joint wear (AL10/AL20)
The RX450h shows accelerated wear of suspension bushes and joints, particularly control arm bushes and ball joints. Affects AL10, AL20; typical independent garage repair cost is £300–£600.
Shock absorber leakage and failure (AL10/AL20)
MOT data shows the RX450h fails at 3.1 times the fleet average for shock absorber damage or severe leakage, particularly on higher mileage vehicles. Affects AL10, AL20; typical independent garage repair cost is £400–£800.
Wheel bearing wear (AL10/AL20)
MOT data shows the RX450h fails at 2.2 times the fleet average for wheel bearing excessive play, typically occurring between 100,000-120,000 miles. Affects AL10, AL20; typical independent garage repair cost is £250–£400.
For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full Lexus Rx450h common problems breakdown.
What to check before buying a Lexus Rx450h
Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a Lexus Rx450h:
Lights & Electrics — check for light unit fault, front or rear fog lamp not securely attached. Suspension — check for suspension joint dust cover severely deteriorated, suspension pin, bush or joint worn.
Beyond the MOT items, ask specifically about brake system warning lights and abs issues and suspension bush and joint wear. These won't show up on a standard MOT but can be expensive to fix — repairs start from £200. A specialist pre-purchase inspection is worth the investment on this model.
Always check the car's full MOT history for patterns — recurring advisories often become failures within 12 months. And verify the service history to confirm maintenance has been kept up to schedule. Enter any reg into our free car check to see the complete picture.
Looking at a specific Lexus Rx450h?
Enter the reg to see its full MOT history, mileage records, write-off status, and finance checks.
Lexus Rx450h MOT FAQs
What are the most common MOT failures on a Lexus Rx450h?
Based on 13,057 DVSA MOT tests, the most common failure is light unit fault — at 8x the national fleet average. Other frequent failures include front or rear fog lamp not securely attached and suspension joint dust cover severely deteriorated.
Is the Lexus Rx450h reliable based on MOT data?
The Lexus Rx450h has 4 MOT failure categories above the fleet average. Specialists also flag brake system warning lights and abs issues as a concern. A pre-purchase inspection and service history check are recommended.
What MOT failures should I expect at high mileage?
The most common high-mileage failures include light unit fault, front or rear fog lamp not securely attached, suspension joint dust cover severely deteriorated.
How do I check a Lexus Rx450h's MOT history?
Enter the registration number into our free car check above. You'll see every MOT test result, advisories and failures, mileage readings, write-off status, and finance checks.
MOT failure data sourced from DVSA bulk test records via data.gov.uk. Ratios compare this model's failure rate against the national fleet average. Known issues sourced from manufacturer bulletins, specialist workshops, and verified owner reports.