TM-9-2320-361-24-1 Field Maintenance Manual Volume 1 for M44A2 Series Trucks
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TM 9-2320-361-24-1 0014 00 0014 00-4 INDICATORS, GAUGES, AND WARNING SYSTEM TROUBLESHOOTING (Contd) Table 1. Indicator, Gauges, and Warning System Troubleshooting (Contd). MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 2. ENGINE TEMPERATURE GAUGE INOPERATIVE NOTE If STE/ICE-R is available, perform NG31 gauge test (WP 0018 00). Test 1. Test coolant temperature gauge operation. 1. Disconnect lead 33 from coolant temperature sending unit. 2. Turn power accessory switch to ON position. 3. Coolant temperature gauge should read minimum temperature. 4. Touch contact end of lead 33 to frame ground. Coolant temperature gauge should read maximum temperature. Test 2. Test battery voltage into temperature gauge. Go to WP 0014 00, table 1, malfunction 1, test 2. Test 3. Test temperature-sending unit. 1. Allow coolant to cool. 2. Set multimeter to RX 1 scale. 3. Start engine (TM 9-2320-361-10). 4. Connect multimeter negative lead to engine ground and positive lead to sending unit. Resistance reading should decrease as engine coolant temperature increases. Test 4. Check continuity of lead 33. 1. Disconnect lead 33 from temperature gauge. 2. Set multimeter to RX 1 scale. 3. Touch negative lead of multimeter to contact end of lead 33 at sending unit. 4. Touch positive lead of multimeter to other end of lead 33. 1. If coolant temperature gauge operates properly, go to test 3 and check sending unit. 2. If coolant temperature gauge does not operate properly, go to test 2. 1. If resistance does not show an decrease as temperature increases, replace temperature sending unit (WP 0107 00). 2. If resistance does show a decrease as temperature increases, go to test 4. 1. If continuity is not present, repair or replace lead 33 (WP 0090 00). 2. If continuity is present, replace temperature gauge (WP 0095 00).