The average premium car today has more than a mile of cables, between 50 and 70 control units and the computing power of 20 advanced PCs. But only the black box unit, the rooftop wifi hotspot and the driver's smartphone can send and receive data beyond the car itself. The black box feeds into the network of sensors and control units in the car, which handle functions such as the airbags and brakes. Carmakers insist on firewalls that segregate the critical internal mechanical parts on the network from the non-critical control units, such as infotainment systems.

Connected points in the car . . .
1 Engine – Ford's new S-Max people carrier comes with an intelligent speed limiter that uses a camera mounted on the windscreen to scan traffic signs and adjust the throttle

2 Headlights – Valeo's matrix beam technology employs front-mounted cameras that detect approaching vehicles and turn on and off individual luminous pixels, so the car has constant full-beam at night without dazzling other drivers.

3 Chassis – VW's adaptive chassis creates a comfortable or sporty feel for drivers, using sensors in the wheels to react to road conditions and adjust the shock absorbers.

4 Brakes – Advanced emergency braking uses front-mounted lasers to detect stationary objects and engage the brakes. Stability technology can also engage the brakes to avoid spin-outs.

5 Suspension – A 2014 wireless update for Tesla owners introduced location-based air suspension, which remembers pot holes and steep driveways and automatically adjusts road clearance.

6 Tyres – Sensors embedded within tyres detect air pressure and temperature. The car can sense if you have a puncture and, linking in with the navigation system, summon a breakdown service or guide you to the nearest garage.

7 Grille – Becomes the eyes of the connected car. Ultrasonic cameras and radar systems power safety features based on the movement of other objects and vehicles, such as automatic emergency braking and adaptive cruise control.

8 Seats – Include sensor mats embedded in the foam that detect the weight of the passenger and tell the airbag how much force to deploy with. Cameras can also be used to create a profile of the passenger and help distinguish adults from children.

9 Head-up display – Many premium cars offer a feature that projects information on to the windscreen as if it is "floating" in front of the eyes of the driver. Information ranges from navigation to pedestrian detection.

10 In-car camera – Carmakers are working on ways of making sure the driver is paying attention at all times. Toyota and GM are both developing eye and head-tracking technology that uses a driver-facing cockpit camera. Other suppliers, including Valeo, are working on facial recognition.

11 Steering wheel – Sensors in the steering wheel can detect heart rate to warn of irregular rhythms, pick up signs of fatigue, anger or nervousness and even – through perspiration in the hands – measure blood-alcohol content.

12 Centre-stack – The hub of the vehicle for media, communication and navigation. Apple and Google have developed platforms.

13 Locks – Modern premium cars offer near-field communication, unlocking the car even if the key is in the driver's pocket. Smartphones can start cars remotely, activate the horn or flash the headlights.

14 Comfort – Many of the latest cars make it possible to control in-car heating or air conditioning from inside the home. Ford is also working with Nest, the smart-home company, on ways of getting the car to talk to the home thermostat.
© Financial Times Limited 2015

. . . and who your car is talking to
Transport infrastructure – Many carmakers are exploring the potential of "intelligent transport systems" that could warn drivers of traffic jams or hazards further up the road. Brussels also wants all new cars sold in the EU to feature an eCall automatic distress signaller to alert emergency services in the event of an accident.

Other vehicles – Vehicle-to-vehicle communication would allow cars to "talk" to each other – say, to alert the trailing driver when the car in front is about to change lanes – or receive motorcycle warnings, helping to increase awareness and safety.

Insurance – "Black box" telematics devices in cars are changing motoring policies, offering insurers more information about how risky their customers are behind the wheel and pushing down premiums for drivers who can prove themselves to be careful.

Manufacturer – Carmakers can wirelessly monitor the inner workings of the car by accessing on-board controllers via the telematics unit. This offers big benefits for manufacturers. Potential recall issues can be spotted early; minor software glitches can be fixed simply with an over-the-air update.

Internet – A wifi hotspot on the roof allows the car to connect to the internet for web browsing, communication or streaming media content. GM's OnStar service offers 4G LTE that allows streaming at 10 times the speed of 3G for up to seven in-car devices.