Mandato del Pacífico Sur
On 1 December 1924, "Komahashi" was again classified once again as a submarine tender, however her primary task for the next several years was that of a survey vessel, charting the area around the Pescadores and the China coast. On 1 October 1931, "Komahashi" was assigned to the Yokosuka Naval District, and was refitted at the Yokosuka Naval Arsenal in early 1932 with more powerful diesel engines and survey ship facilities, a process that lasted until November 1932. Upon re-launching, she surveyed around the Luzon Strait, the South Pacific Mandate, the Kuril Islands and the Kamchatka Peninsula, collecting data on ocean currents, salinity, subsea topography and fisheries resources. One of her discoveries was the Komahashi Seamount, an underwater volcano at the northern end of the Kyushu–Palau Ridge in the Philippine Sea.