Owners usually say where they were. Across 1,109,342 complaints, three locations appear often enough to compare properly.
| Where it happened | Complaints | Ended in a collision |
|---|---|---|
| Car park | 17,191 | 12.7% |
| Driveway | 18,812 | 11.9% |
| Motorway | 77,671 | 5.1% |
| All complaints | 1,109,342 | 5.8% |
The motorway, where everything happens at seventy miles an hour, has the lowest crash rate of the three. The car park has the highest.
The difference is what the fault does to the car
At speed, almost every fault takes something away. Power, brakes, steering assist, a tyre. The driver loses capability and reacts by slowing down and pulling over, and most of the time that works — there is space, everyone is travelling in the same direction, and the shoulder exists precisely for this.
In a car park the common faults do the opposite. They add motion that nobody asked for. The component list for these complaints is led by the power train at 3,596 and steering at 3,256, and the descriptions are of cars that moved when they should have been still.
A vehicle that surges forward from a standstill has almost no distance in which to be corrected. There is a wall, another car, or a person within a few feet, and the driver has under a second.
The cars that move on their own
19,028 complaints specifically mention the car being in park. 1,331 describe it rolling away.
These are mechanical failures of the parking pawl, the cable, or the interlock that is supposed to prevent shifting out of park without a foot on the brake. They produce a stationary car that becomes a moving one with nobody in a position to stop it — sometimes with the driver stepping out, which is how these turn into injuries rather than dents.
It is the same mechanism behind another figure in the record: 14% of parking brake complaints end in a crash, roughly double the overall rate.
Why the motorway number is low
Two reasons, and one of them is about reporting rather than risk.
A fault at speed that does cause a crash produces a police report, an insurance claim and sometimes an injury — and those complaints are filed much later, if at all. The ones filed promptly are the ones where the driver pulled over safely and was annoyed.
The second reason is real: motorways are engineered for failure. Wide lanes, no oncoming traffic, a hard shoulder. A car park is engineered for packing vehicles close together.
What to take from it
If a car has ever moved when it should not have, or hesitated and then surged, that is not a minor complaint to be mentioned at the next service. It belongs in the category of faults that hurt people at walking pace.
On a used car, the specific checks are cheap: shift to park on a slope and see whether the car settles onto the pawl with a clunk or keeps creeping, and apply the parking brake alone on the same slope. Then check the VIN for open recalls — shift interlocks and parking pawls are a recurring recall subject, and the repair is free.
Frequently asked questions
Where do vehicle faults most often cause a collision?
Car parks and driveways. Complaints describing a car park involve a collision 12.7% of the time and driveways 11.9%, against 5.1% for motorways and 5.8% overall.
Why is a fault at low speed more likely to cause a crash?
Because of what the fault does. At speed most failures remove capability, and the driver slows and pulls over. In a car park the common failures add unrequested motion — a surge or a roll — with a wall, a car or a person a few feet away and under a second to react.
What should I check on a used car for this?
Shift into park on a slope and confirm the car settles with a clunk rather than creeping, then test the parking brake alone on the same slope. Shift interlocks and parking pawls are a recurring recall subject, so check the VIN for open recalls as well.
Denis Kataev is a serial solopreneur and the founder of ForCar. With 15+ years in software engineering and 10 years in SEO, he builds data-driven products end to end — backed by a sharp eye for design. At ForCar he mines proprietary vehicle datasets, turning raw numbers into buying advice you can actually trust.
Keep reading
All articles →
Two Thirds of 2022 Cars Failed the Seat Belt Reminder Test. By 2026 It Was 18%.
A rating that measures a chime sounds trivial until you look at what it is for. Nearly half of people killed in crashes are unbelted, and the cheapest available intervention is a car that refuses to shut up.
54,604 Complaints Describe Something That Almost Happened. The Power Train Leads.
Safety data counts what happened. A large set of complaints exists specifically to report what did not, and those reports arrive from systems that rarely appear in crash statistics at all.
The Passenger Side Was Tested Fifteen Years After the Driver's. It Scores Better.
For over a decade, one side of the car was crash tested and the other was assumed to match. When the assumption was finally checked, the results said something unexpected about how safety engineering responds to being measured.
Mark ForCar as a preferred source and our data shows up first in your Google results. One click, no account.