Manned by a United States Coast Guard crew, "Carson City" departed Los Angeles, California, on 19 July 1944, for Espiritu Santo and Milne Bay, New Guinea, where on 13 August 1944, she reported for patrol and escort duty in the New Guinea area with the United States Seventh Fleet. She took part in the unopposed landings on Morotai on 16 September 1944, then took part in guarding ships, men, and supplies being assembled for the landings on Leyte in the Philippine Islands. She herself sailed for Leyte Gulf from Humboldt Bay, New Guinea, on 16 October 1944, supporting the first wave of reinforcements for the Northern Attack Force at Leyte. On 22 October 1944, she accompanied her charges into the landing area, and next day began a voyage escorting the empty ships back to Humboldt Bay.