ARMY TM 9-6115-670-14&P 4-144 4.56.   SPEED SENSOR. This task covers: a. Test b. Adjust c. Replace INITIAL SETUP Tools General Mechanic's Tool Kit (Item 1, Appendix B) Multimeter Equipment Conditions MASTER ON-OFF switch on APU control unit   set to OFF. MASTER ON-OFF switch on APU controller set to OFF. Materials/Parts Speed Sensor Field Gauge Strap, Tiedown, Elect. (Item 22, Appendix F) Radiator overflow tank, removed (para 4.28., steps a- c). Air deflector removed (para 4.18., step b). TEST a.  Remove connector J6 (7) from governor speed control (8). b.  Measure resistance of speed sensor.  Resistance should be 750 ohms +/- 250 ohms. c.  Replace if defective. ADJUST a.  Remove connector J6 (7) from the governor speed control (8). b.  Cut and remove tiedown straps as necessary to remove speed sensor wire (6). c.  Remove sensor (7) and sensor securing nut (1); remove sensor (3) from engine bell housing (5). d.  Observe that flywheel gear tooth (4) is aligned with access hole (2) in engine bell housing from which speed sensor (3) was removed. e.  Install sensor (3) into engine bell housing (5) and ensure that sensor is aligned and makes contact with crest of engine flywheel gear tooth (4). f.   Turn speed sensor ccw one and a half turns, backing it out. CAUTION Take   care   not   to   cut   wires   or   other   APU components when removing wire ties.