Satellite navigation systems can take a lot of stress out of driving, but some engineering experts are now warning that these systems could actually be a source of stress for your car, or your battery in particular.
The Royal Automobile Club (RAC) in Britain says that more than half of all call-outs for flat batteries last year were found to have been caused by electrical accessories draining the power.
And it's not just retrofit satellite navigation systems that are causing the problem: iPods, DVD players and mobile phone chargers are all causing the "premature failure of thousands of car batteries".
The British motor industry organisation estimates that sales of satellite systems and in-car entertainment systems, which are fitted after the car is purchased, have gone from 100,000 in 2001 to almost two million in 2005. The RAC is now recommending that car owners upgrade power packs if they are running all this extra equipment in their cars.
The battery manufacturer, Varta, says the problem first became apparent in the US, where those involved in customising cars noticed an increase in car battery failure.
Varta says the battery upgrade required should be the same as the car manufacturer would have used if the equipment fitted had been standard on the car. The company points out that with extras such as electronic reclining rear seats and even a heated steering wheel now being fitted to some luxury cars, an additional battery is required to run them.
"The power requirement of many of the models launched in Detroit and Geneva recently, such as the Audi Q7 V12 TDI and the Lexus LS 460, can only be met by batteries fitted in the factory," a Varta spokesman says.
These problems are not yet so evident in Ireland. The AA, which attends to some 160,000 call-outs a year, says 25 per cent of those calls are related to battery problems, but there has not been a "surge" in battery problems because of satnav systems.
"Perhaps it is because the roll-out of satellite navigation has been much slower in this country," according to the AA's Conor Faughnan.