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 00-8 INDICATORS, GAUGES, AND WARNING SYSTEM TROUBLESHOOTING (Contd) Table 1. Indicator, Gauges, and Warning System Troubleshooting (Contd). MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 4. OIL PRESSURE GAUGE INOPERATIVE NOTE If STE/ICE-R is available, perform NG 31 gauge test (WP 0018 00). Test 1. Test oil gauge operation. 1. Disconnect lead 36 at oil pressure sending unit. 2. Turn power accessory switch to ON position. 3. Oil pressure gauge should show minimum pressure. 4. Touch contact end of lead 36 to frame ground. Oil pressure gauge should show maximum pressure. Test 2. Test battery voltage to oil pressure gauge. Go to WP 0014 00, table 1, malfunction 1, test 2. 1. Set multimeter to RX 1 scale. 2. Connect negative lead to frame ground on engine. 3. Touch positive lead to contact of oil pressure sending unit. Resistance should measure less than 1 ohm with engine off (no oil pressure). 4. Remove oil pressure sending unit. (WP 0106 00). 5. Install mechanical gauge. 6. Start engine and check oil pressure on mechanical gauge. Test 4. Test continuity of lead 36. 1. Disconnect lead 36 from oil pressure gauge. 2. Set multimeter to RX 1 scale. 3. Touch positive lead of multimeter to one end of lead 36 and negative lead of multimeter to other end of lead 36. 1. If oil pressure gauge operates properly, go to test 3. 2. If oil pressure gauge does not operate properly, go to test 2. 1. If resistance is 1 ohm or more, replace oil pressure sending unit (WP 0106 00). 2. If resistance is less than 1 ohm, continue with step 4. 1. If oil pressure is 10 psi or above at idle, replace oil pressure sending unit (WP 0106 00). 2. If oil pressure is less than 10 psi at idle, gauge is accurate. Go to WP 0008 00, table 1, malfunction 13, to diagnose engine. 1. If continuity is not present, repair or replace lead 36 (WP 0090 00). 2. If continuity is present, replace oil pressure gauge (WP 0095 00).