Hyundai Mobis Co., South Korea's largest auto parts maker, said Monday its fourth-quarter net profit edged up 0.5 percent from a year earlier due to overall increase in sales.

The bottom line came to 905.2 billion won ($834.9 million) in the October-December period from 900.3 billion won a year earlier, the company said in a regulatory filing.

The company said sales jumped a solid 11.1 percent to 9.19 trillion won and its operating profit gained 5.2 percent to 870.7 billion won. The company's sales figures for the fourth quarter of 2012 stood at 8.28 trillion won, with operating profit hitting 827.7 billion won.

"Rise in sales of vehicles that use Hyundai Mobis parts helped numbers" the company said in a press release.

For the whole of 2013, net profits dipped 4.1 percent to 3.39 trillion won from 3.54 trillion won tallied in 2012, with operating profit moving up 0.6 percent on-year to 2.92 trillion won. Sales earnings topped 34.19 trillion won for an 11.1 percent increase from 30.78 trillion won reported for the year before.

On weak annual numbers, the company said disruptions in local production, rise in labor costs and unfavorable exchange rates affected earnings. Labor strikes halted production in the third quarter of last year.

It added that more research and development outlays hurt profits to some extent.

The company, which is part of the Hyundai Motor Group, the world's fifth-largest carmaker and South Korea's second-largest family-run conglomerate, said despite the modest decline in net profits, its key bread-earner, module production, was up a sharp 12.3 percent for the whole of 2013 to 27.02 trillion won, with parts sale, for repairing vehicles already on the road, gaining 5.6 percent to just under 6.22 trillion won.

Among module sales, high-tech value-added parts made up roughly 9.5 trillion won of total sales for the company last year. 

Modules made by Hyundai Mobis include chassis, the area around the driver seat such as the steering column and dashboard, and the so-called front-end modules. A front-end module refers to the section of a car like the bumpers, headlights and parts related to air-conditioning and the radiator.

Hyundai Mobis has production facilities in all regions where Hyundai Motor Co. and Kia Motors Corp. have assembly lines.

Sales from overseas plants in China jumped 22.8 percent last year, with an increase of 11.9 percent reported for South and North American continents. Numbers for Europe moved up 12.8 percent on-year, it said. (Yonhap News)