What Car? goes cold-weather testing

They're having a mild winter in northern Sweden, 300 kilometres inside the Arctic Circle, this year.

Night-time temperatures are only -13C, way above the seasonal average of around -25C. During the day it can reach a balmy freezing point.

This is not good news for the car manufacturers who go there to conduct cold-weather testing, pushing mechanical and electrical components to extremes to find any weaknesses.

Volvo was the first car company to evaluate its cars in extreme cold, back in the 1960s. These days, it is part of the development regime of every manufacturer, and the tests have become ever more sophisticated as the number of electrical features on cars has grown.

At the end of January, we joined a Volvo team in the far north of Sweden, just a few hundred metres from the Norwegian border, to find out what goes on.

Life in the freezer...
Those initial cold-weather tests nearly 50 years ago were on a small scale, mainly to assess the cars' ability to start and stop in extreme temperatures.

Today it has turned into a regimented programme. Tests are conducted between late November and early April, and the drivers are locals as well as Volvo engineers. The cars will cover the equivalent of five times around the world.

'We are acting as the customer. Everything should function as the customer expects, even in these temperatures,' says Stefan Andersson, Volvo's field testing manager.

Andersson's team is not just looking to see whether engines will start in ultra-low temperatures, or to check that four-wheel-drive and electronic safety systems operate correctly.

Windscreens should clear in a fixed time and climate control systems must maintain a specified temperature difference between passengers' heads and feet.

There should be no loss of visibility, and the steering and brakes must deliver sufficient feel. Even electric seat mechanisms must function as normal.

'It is much, much more complex than it used to be because of the arrival of multiplex wiring systems and the number of electronic items on modern cars,' says Andersson. 'If we had a problem in the past, we could fix it with what we had in our toolboxes. These days we need to be software engineers.'

and life in 'The Fridge'
And when it's not cold enough to go through the planned routine? That's when the cars go in The Fridge, a container that can cool them overnight to -30C.

The next morning the doors are forced open, the engine is cold-started from scratch and the cars have to be ready for the day's tests.

Mind you, that's not always necessary. The record low in this part of Sweden is -52C. 'We might have a bit of trouble getting them to start in those conditions,' says Andersson with a wry smile.