What was found
AIR TURNBACK DUE TO LT MAIN TANK FUEL INDICATOR AND TOTALIZER GOING BLANK. CHECKED FUEL QTY UNIT, FOUND NO PRESENT FAULT. IN FAULT HISTORY "00", FOUND LM TU1 2, 3, 4, 5 CONTAMINATED, LM TU 10, 11, 12, 13, 14. OPEN LOZ OR HIZ WIRE, LM CONPENSATOR CONTAMINATED, LM DENS CONTAMINATED OR RESISTOR. REPLACED FUEL QTY UNIT IAW AMM 28-41-08, TEST PASS. ACFT OK FOR SERVICE.