Electronic Stability Control

All ESC systems are created equal, but some are more equal than others?

All the new cars tested to date have passed this demanding ESC dynamic test. This shows that these cars, which are sold as having ESC systems fitted, also have the functionality to operate and maintain control of the car in this severe manoeuvre. However, they do not all perform the same way, and some differences between the systems are revealed.

These differences between the ESC systems are not apparent in terms of the assessment criteria as set out in the GTR, since all the vehicles pass. However, they may give some effect in other scenarios where ESC should intervene. For example, it could be worrying if a vehicle is allowed to develop large slip angles before ESC intervenes, as the risk of lane departure at the road edge might increase the risk of a collision.

One specific example is the Vauxhall Meriva, which showed a greater speed reduction during the test manoeuvre compared to most other vehicles. The ESC system is braking individual wheels in order to maintain stability of the car, which also reduces the overall speed of the car. In the event of a collision, perhaps the braking by the ESC system might also help to reduce the severity of the impact.

2010 ESC Fitment Ratings


In 2006, Thatcham began to produce fitment ratings for ESC, and found that only 40% of UK models were being sold with ESC fitted as standard. Now, after 5 years, this figure has increased to 75%. We are now beginning to see the increase in standard fitments that is required by the impending regulatory requirements.