TROUBLESHOOTING (Continued)

TM 9-4910-663-34 Table 2-5. TROUBLESHOOTING (Continued) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION If DC AMMETER FIELD CURRENT meter M7 indicates zero amperes, replace DC AMMETER FIELD CURRENT RANGE switch S30. Step 5. Adjust VARIABLE LOAD control R32 to provide 3 ampere indication on DC AMMETER FIELD CURRENT meter M7. Then, set DC AMMETER FIELD CURRENT RANGE switch S30 to X1 position, and check to see that DC AMMETER FIELD CURRENT meter indicates 3 amperes. If DC AMMETER FIELD CURRENT meter M7 indicates zero, replace DC AMMETER FIELD CURRENT RANGE switch S30. Step 6. Adjust FIELD CURRENT 0-30 AMPS (MAX) control R26 counterclockwise, and check to see that indication on DC AMMETER FIELD CURRENT meter M7 decreases with adjustment of control. If indication does not decrease, indication varies erratically, or indication drops off suddenly, replace FIELD CURRENT 0-30 AMPS (MAX) control R26. Step 7. Set FIELD CURRENT 0-30 AMPS (MAX) control R26 and FIELD CURRENT (fine) control R27 fully clockwise. Adjust VARIABLE LOAD control R32 to provide 3 ampere indication on DC AMMETER FIELD CURRENT meter M7. Set FINE CONTROL 0-5 AMPS (MAX) switch S29 to ON position. Rotate FIELD CURRENT (fine) control R27 counterclockwise and check to see that indication on DC AMMETER FIELD CURRENT meter M7 decreases smoothly toward zero. If there is no current indication, perform a continuity check of CB10, R27 and associated wiring (See FO-1). Replace defective component. If current indication does not decrease, or if indication varies erratically, replace FIELD CURRENT (fine) control R27. 13. DC AMMETER LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE CURRENT METER CIRCUIT a. DC AMMETER LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE CURRENT METER CIRCUIT INOPERATIVE OR OPERATES ERRATICALLY DURING TESTS OF EXTERNAL COMPONENTS. 2-48