Using vegetable peeler, remove peel in strips from limes and lemon (green and yellow parts only). Cut peel into 1 x 1/8-inch strips. Place in medium bowl. Squeeze enough juice from limes and lemon to measure 2 tablespoons lime juice and 2 tablespoons lemon juice. Add to bowl with peel. Add corn kernels, jalapeños, oil, and 3/4 teaspoon coarse salt; stir to blend. Cover and chill at least 2 hours to allow flavors to blend. Season to taste with more coarse salt, if desired. DO AHEAD: Can be made 1 day ahead. Keep chilled. Bring relish to room temperature before serving.