PREHEAT grill to medium heat, or preheat broiler. Place sweet potatoes and water in microwavable dish; cover. Microwave on HIGH 5 minutes; drain.
MIX barbecue sauce, juice, sugar and pepper until well blended.
PLACE turkey and sweet potatoes on grill grate or rack of broiler pan. Grill or broil 10 to 12 minutes or until turkey is cooked through and potatoes are tender, turning occasionally and brushing with barbecue sauce mixture.