Tests shows new Google Maps speedometer feature ‘inaccurate’

A car expert has tested the accuracy of the navigation app Speedos and has been shocked at the results.

A road test of Google’s new speedometer feature on its maps app has found it to be “completely inaccurate”, and could put motorists at risk of falling victim to fines.

Google began to roll out the feature on Apple CarPlay and Android Auto devices last month, but note on its website the speeds shown are “for informational use only”.

Paul Maric from Car Expert cited exploding speeding fines in his home state of Victoria to see just how much drivers could trust the technology they are relying on more and more.

He compared readings from navigation apps Google Maps, Waze and a car’s own speedometer to the actual speed of the vehicle using a laser reader.

Not knowing your actual speed could lead to fines. Picture: NewsWire/ Monique Harmer

He said the results were surprising. Google Maps consistently displayed 2km/h under the actual speed, but Waze matched the laser’s mark.

“I use Waze pretty consistently. And touch wood, haven’t got a speeding fine yet. So we thought we’d put it to the test,” Mr Maric said.

“And when Google Maps came up just being completely inaccurate to the point where you could potentially land yourself in a situation where you get a speeding fine, we’re pretty surprised by that.

“Especially since this is a new feature that they’ve added recently to Apple Car Play with that sort of speed readout for Google Maps.”

Car Expert used a pro laser reader to measure speeds. Picture: carexpert.com.au

Car Expert’s testers used a Ford Mustang for the trial and investigated at speeds of 80km/h and 100km/h.

Both Google Maps and Waze rely on satellites to track the pace at which a vehicle moves between points and display a predicted speed on the in-car display.

Poor weather conditions and driving in tunnels can have an impact on the accuracy of such apps.

On its website, Google says: “Speedometers shown in the Google Maps app are for informational use only.

“Make sure to use your vehicle’s speedometer to confirm your actual driving speed.”

The Waze reading. Picture: carexpert.com.au

The Google Maps reading. Picture: carexpert.com.au

Mr Maric said the differing results between Google’s app and Waze was “funny”, considering the tech giant bought the latter for $1.3 billion in 2013.

“And you would have thought that Google would just use whatever technology is in Waze to calculate speed as well,” he said.

“But it appears that they’re doing something completely weird and different here, because it was so erratic, it was jumping up and down constantly, to the point where you just couldn’t rely on it to accurately tell your speed while you’re driving.”

Car speedometers can also be wide of the mark.

For Australian vehicles, car speedometers have to be tuned within a certain range but can be inaccurate with several clicks.

Car Expert’s results showed that at both 80km/h and 100km/h, the car’s speedometer was out by 4km/h and 5km/h, respectively.

“A lot of people don’t know that small changes to their car, like tyres and rims can actually affect your speedo’s accuracy,” Mr Maric said.

“So if you have a car that comes out of the factory with a fairly accurate speedo, the second you go making modifications … you can actually find that the speedo is no longer actually doing the speed that it says it’s doing.”