TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 1 Download
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TM 9-2320-387-24-l REFERENCE INFORMATION GLOW PLUGS CIRCUIT - Refer to the functional flow schematic. If the glow plug controller is shorted (continuity from pin 6 to pin 3) the glow plug power relay will always be energized and the glow plugs will always be drawing current. BATTERY CURRENT STEIICE-R TEST 80 1. Start Test 80. Battery Current. 2. Displayed reading is in amps. The reading will be greater then 30 amps, depending on how many accessories you have on. Since the glow plugs draw current without the glow plug controller connected, there must be a short in the harness or a stuck relay in the PCB. If there were a short in the harness directly to the glow plugs, the glow plugs would have burned out long ago and you wouldn’t be here. The only other short in the harnessthat 3O 4. so 0 0 l 6 lo would make the glow GLOW PLUG CONTROLLER plugs turn on without the HARNESS SCHEMATIC glow plug controller installed would show. up as battery voltage at pin 6 of the controller’s connector. Replace PCB (para. 4-4). Check the end of the harness at the PCB, glow plugs, etc., for shorts. Repair whatever you can. If you don’t see anything wrong, the short must be in the main body of the harness. which means that you have to replace the harness. WARNING Disconnect negative battery cable before disconnecting and reconnecting PCB harness. WARNING There is battery voltage at the PCB at all times. Failure to disconnect battery cable will result in damage to equipment or injury to personnel. Repair or replace wiring (para. 4-80). BAITERY CURRENT MULTIMETER 1. Set the voltmeter to a DC volts scale of about 1 v0n. 2. Connect the BLACK lead to the battery side of the current shunt and the RED lead to the other end of the current shunt 3. Current shunt voltage is proportional to battery current, 100 millivolts = 1,000 amps. To get current, multiply miltiilts x 10. DC VOLTAGE O-45 VOLTS STE/lCE-R TEST 89 1. Connect RED clip to the indicated test point, BLACK clip to negative or ground. 2. Stan Test 89. DC Votts. 3. Displayed reading is in volts. VOLTAGE MULTIMETER 1. Set the voltmeter to a DC volts scale of at least 40 volts. 2. Connect the RED lead to positive and the BLACK lead to negative. 3. Be sure to read the correct scale. 2-297