Troubleshooting Procedures

TM 5-6350-264-14&P-10 NAVELEX EE 181-AA-OMI-110/E121 C-9412 T.O. 31S9-2FSS9-1-10 Table 5-2. Troubleshooting Procedures - Continued Trouble Probable cause Corrective action 4. (Cont) c. (Cont) 28 +2 vdc. Turn mode switch to TEST/RESET and then to SECURE. d. Incorrect a. Set multimeter to dc volts and connect supply positive meter lead to PC board A1-TP1 voltage or (brown), and negative lead to chassis bad tamper (ground). Turn mode switch to SE- circuitry. CURE and ensure that no alarms are activated. Meter should indicate 18.5 to 21 vdc. b. If meter indicates less than 1 vdc, turn mode switch to ACCESS. Connect positive meter lead to power supply TB2-3. Meter should indicate 20 + 1 vdc. Con- nect meter lead to TB2-5. Meter should indicate 5 +0.25 vdc. Con- nect meter lead to TB2-2. Meter should indicate 28 +2 vdc. c. If any of these indications are not correct, turn off switch S1 on power supply. Check wiring for poor or loose con- nections, broken wires, or frayed in- sulation. Repair or replace any bad wiring. d. If wiring is good, replace power supply. (1) To remove power supply, pull main, circuit breaker to remove 120 vac from CU. Disconnect wires from battery. As battery is heavy, lift and turn to remove it from bottom of CU enclose- ure. Tag and disconnect wires from TB2 and TB4. Remove screws that secure cover, and remove cover. Tag and disconnect wires from TB1. Care- fully remove screws that secure power supply to side of CU enclosure. Be careful not to drop it inside CU. Note cable clamp under screw near TB4 (bottom front). Support power supply and turn it so wires can be tagged and disconnected from TB3 on bottom of power supply. 5-57