TM-9-2320-280-34 HMMWV Direct Support & General Support Maintenance Manual Download
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6-3.2. 100 AMPERE ALTERNATOR (12342944) TESTING AND REPAIR (Cont’d) Table 6-A. No-Load Test. AMPS VOLTS DIAGNOSIS High Low Test bench battery is discharged (or defective). Allow to charge (or replace). High Normal Give time to stabilize while monitoring VOLTS. If VOLTS rise above normal range (26-30 volts), regulator and/or tube assembly must be replaced. If AMPS fall, charging system is OK. High High STOP TEST. Regulator and/or tube assembly must be replaced. Refer to Static Testing. Low Low Alternator and/or regulator must be repaired or replaced. Refer to table 6-A.2. Low Normal Regulator OK. Refer to table 6-A.1. Low High STOP TEST. Bench malfunction or wiring error. TM 9-2320-280-34 Change 1 6-18.17 6. Perform no-load test. Set test stand battery circuit selector to 24 VDC, IGN switch to ON, and start varidrive. Observing the DC voltmeter output voltage and tachometer rpm, increase speed until tachometer reads 5000 rpm. Record voltmeter reading and refer to table 6-A for diagnosis.