On June 4, 2001, at 1530 central daylight time, a Cessna 172L, N18PF, made an emergency landing in a field after a loss of engine power 17 miles north of Picayune, Mississippi. The flight was operated by the pilot under the provisions of Title 14 CFR part 91 with no flight plan filed. The airplane was sustained substantial damage, and the pilot received minor injuries. The flight departed Eufaula, Alabama, at 1315 central daylight time. According to the pilot, he was enroute from Eufaula, Alabama, to Bogolusa, Louisiana, when the engine lost power and quit. During an emergency descent out of 4500 feet, the pilot attempted to restore full engine power but failed. The pilot then executed a forced landing to a nearby field. During the emergency descent to land in a hilly farm field, the airplane's left wing struck a utility pole severing the left wing from the airplane. Onsite examination of the airplane revealed the fuel selector was found on both, and the main auxiliary fuel pump switch was in the "off" position. Further inspection showed the shoulder harness on the pilots side were not in use at the time of the accident. The Cessna had two additional auxiliary fuel tanks installed with a Supplemental Type Certificate in August, 2000. These auxiliary fuel tanks are operated by auxiliary fuel pumps. Each fuel tank held approximately 11.5 gallons. During the onsite wreckage examination, the two main fuel tanks were found to be empty as well as the right auxiliary fuel tank. The left auxiliary fuel tank had approximately 11.5 gallons, of fuel remaining. The left auxiliary fuel pump was removed and it was full of fuel. There were no sediment or contamination found during the inspection. The pump was tested with a 12 VDC source, the left auxiliary fuel pump operated and pumped fuel. An in line fuse was found under the instrument panel, and it had failed. The pilot was unable to switch to the left auxiliary fuel tank. The pilot stated that when he attempted to transfer fuel from the left auxiliary fuel tank, the indicator light did not come on and no fuel transfer was observed. The fuses to the auxiliary fuel tanks are not accessible to the pilot in flight, this resulted in the lack of ability to check them for condition or replace them. The pilot did not refuel the airplane before takeoff, nor did he terminate the flight once he was aware the transfer of fuel was not possible from the left auxiliary fuel tank.