A tragic incident on the M25 motorway has exposed a critical design flaw in the world's best-selling car, the Toyota Corolla, leading to a woman's death after her anti-lock brake system failed to function following a tyre detachment.
The Fatal Incident on the M25
Lisa Bowen, 48, died from traumatic head and spinal injuries after her Toyota Corolla collided with a parked lorry on the hard shoulder of the M25 in Surrey. The crash occurred on January 11, 2022, between junctions eight and nine, after her vehicle suffered a tyre detachment.
An inquest held in Woking, Surrey, during August heard that Ms Bowen's car became damaged, forcing her to pull over. Despite pressing the brake pedal five times, she was unable to reduce her vehicle's speed of approximately 40mph. The car's anti-lock brake system (ABS) had activated, but instead of helping, it operated to reduce the braking effect almost entirely.
How the ABS System Failed
Vehicle experts explained to the coroner that the failure resulted from a specific scenario the system's designers had not adequately anticipated. Following the tyre detachment, the speed of the wheel with the missing tyre was 'much higher' than the other three wheels.
The anti-lock system, manufactured by Advics, falsely interpreted this data. It identified the problem as lying with the three slower, functioning wheels rather than the single damaged one. This misinterpretation caused the system to activate and drastically reduce the car's braking capability, leaving Ms Bowen helpless.
The inquest heard that a tyre warning light had 'probably' appeared on the dashboard, but it was not possible to confirm whether Ms Bowen had seen or responded to it. She continued driving for several miles, causing further damage to the tyre's tread and sidewall before the detachment.
Coroner's Report and Future Safety
Richard Travers, the senior coroner for Surrey, subsequently wrote a Prevention of Future Deaths report. He stated unequivocally that 'there would have been time and distance for the Toyota to have stopped before the collision' if the brakes had worked effectively.
The crash happened just 17 seconds after the tyre detached and 10 seconds after Ms Bowen moved onto the hard shoulder. The Toyota ultimately collided with the lorry at a speed of 37.9mph.
Mr Travers noted that the company behind the ABS, Advics, has since developed an improved system. The new design is better able to recognise when one wheel's speed is so different from the others that its data should be ignored. However, he cautioned that these improvements are not foolproof, as the vehicle's acceleration or deceleration can still affect this function.
This tragic case highlights a rare but deadly consequence of a safety system failing in an unanticipated real-world scenario, raising important questions for vehicle design and regulation.
