Skip advert
Advertisement

Car Tech A to Z: O is for odometer and occupant sensors

The letter O in our A to Z of car tech series explores odometers and occupant sensors

The technology contained within the modern motor car can be both fascinating and slightly baffling. Most such technology exists to make our cars safer, more efficient and just better than ever to drive but some of it can be quite confusing for the average motorist. In this A to Z series we will attempt to unravel the mystery of technology that is the modern motor car. This week, we’re visiting the letter O…

Advertisement - Article continues below

O is for…odometer. Also known as a mileometer, an odometer is simply a device that measures how far you’ve travelled and it’s thought to have been invented as long ago as 287bc by Archimedes of Syracuse.

An odometer can be either digital or mechanical, although in most modern cars the odometer works electronically by simply logging vehicle speed and then calculating the distance travelled.

O is for…occupant sensors. Fitted to all modern cars, occupant sensors determine whether a seat is unoccupied or not and, in some cases, not only asks a passenger to put a seatbelt on, but also works in conjunction with the airbag system to establish how heavy an occupant is – to then work out how far and how fast to deploy the airbags in the event of an accident.

The system consists of a weight sensing pressure pad mounted beneath the front passenger seat – a set belt tension sensor – a small ECU that runs the system beneath the front passenger seat – and an airbag status indicator lamp, mounted in the roof console.

Thanks to occupant sensor systems, never before have we been so safe when travelling in our cars.

Next, the letter P...

A-Z of car tech
Skip advert
Advertisement
Continue Reading

Find a car with the experts

Skip advert
Advertisement

Most Popular

Ford Fiesta set to return? Icon could be reborn with a little help from Volkswagen
Ford Fiesta exclusive image

Ford Fiesta set to return? Icon could be reborn with a little help from Volkswagen

The Ford Fiesta could be coming back from the dead, and our exclusive image previews how it might look
News
2 May 2025
New Renault 4 2025 review: as good as the Renault 5 with the bonus of extra space
Renault 4 - front

New Renault 4 2025 review: as good as the Renault 5 with the bonus of extra space

The new Renault 4 takes everything that's good about the Renault 5 and adds extra cabin and boot space
Road tests
2 May 2025
New 2025 Kia PV5 van starts from a tempting £22,645
Kia PV5 Cargo on display at Commercial Vehicle Show - front 3/4

New 2025 Kia PV5 van starts from a tempting £22,645

All-new entry into the van market promises competitive pricing and comes with a range of up to 247 miles
News
30 Apr 2025