South Korea plans to resume deployment of a new model of amphibious armoured infantry fighting vehicle, the K-21, in April this year.
The K-21, developed in 2007, was suspended from service last year following the sinking of one of the vehicles during a river-crossing drill.
According to an investigation conducted by military auditors, the vehicle had design and mechanical flaws including a drainage pump and the waterproof seal of the vehicle's hull.
Military officials said the replacement of all faulty parts would be completed by February.
"We have fixed all problems through four rounds of testing. After a final test in March, deployment will resume in April," a Defence Acquisition Programme Administration official said.
South Korea has spent $80.3m developing the vehicles and plans to deploy 100 K-21 vehicles this year, according to Yonhap News.
The vehicle is equipped with a stabilised 40mm cannon, a 7.63mm machine gun and a launcher for anti-tank guided missiles.
The 26t K-21 can carry three crew members and travel at a speed of 70km/h.