BMW Australia puts brakes on speed-recognition technology

German luxury car maker BMW has stopped selling its speed recognition technology in Australia because of a number of discrepancies that have exceeded the legal limit by as much as 40km/h – enough for drivers to lose their licence for up to three months in some states.

The $700 option on the flagship BMW 7 Series limousine and the 5 Series wagon uses a tiny camera in the windscreen to scan the road ahead and 'read' speed limit signs.

The system also relies on speed limit data stored on the car's built-in navigation system.

The speed limit of each road is displayed next to the actual traveling speed of the car – but the system does not apply the brakes and the onus is on the driver to obey the law.

However, numerous errors on the navigation system have seen the car display a speed that is higher than the legal limit.

On a vehicle tested by the Carsales Network yesterday (Thursday), a BMW 7 Series displayed a legal limit of 110km/h but the sign-posted limit was 70km/h. Other inaccuracies we experienced included a display of 100km/h in an 80km/h zone.

Although BMW warns drivers that they are obliged to obey road signs – not the speed limit displayed by the car – it has withdrawn the system to avoid possible legal claims.

BMW customers who have paid for the system will receive a $700 refund when it is disabled.

BMW Australia estimates there are "a few dozen" cars in customer hands since the technology became available locally in January this year, but there are about 500 vehicles in dealer stock that will also have the system disabled until it is fixed.

BMW Australia spokesman Piers Scott told the Carsales Network: "We have had a number of discrepancies and we want to get them ironed out before we re-introduce the system."

The errors have occurred despite BMW technicians from Munich testing the system on Australian roads three times in the past three years.

"In our experience, Australia has a higher number of speed changes than most other countries and has some unique challenges. We are trying to get it fixed as soon as possible but we don't have an estimated time-frame at this stage."

He said there would be no hardware change to the vehicle, simply a software change.

In another example experienced by the Carsales Network this week, the BMW regularly displayed 40km/h when in school zones – outside school times.

When we tested the system in Europe two years ago (when it was released), the car also over-estimated the legal speed permitted in a narrow side lane. The posted limit was 20km/h but the car said the limit was 30km/h.

"At no point do we tell customers to rely on the car's information," said Scott. "It is a supplementary aid, a guide only, but we do want greater accuracy for our BMW customers."

BMW said it was unaware of anyone being booked in Australia because of an incorrect speed limit displayed by the car.

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