TM 9-2320-272-24-1
Table 2-3. Electrical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
33. LOW AIR PRESSURE WARNING BUZZER WILL NOT SHUT OFF (AIR PRESSURE GAUGES AT NORMAL SYSTEM
PRESSURE)
Test 1. Test resistance at low air pressure switches.
Step 1. Start engine (TM 9-2320-272-10) and allow air pressure to reach normal operating
pressure.
Step 2. Disconnect leads 578 and 578A from low air pressure switch A.
Step 3. Set multimeter to RX4 for resistance reading.
Step 4. Touch positive lead of multimeter to contact end of pressure switch A.
Step 5. Touch negative lead of multimeter to other contact end of pressure switch A.
a. If resistance is 300 ohms or less, go to step 6.
b. If resistance is more than 300 ohms, replace low air pressure switch (para. 3-86).
Step 6. Connect leads 578 and 578A to low air pressure switch A.
Step 7. Disconnect leads 57 and 578A from low air pressure switch B.
Step 8. Touch positive lead of multimeter to contact end of pressure switch B.
Step 9. Touch negative lead of multimeter to other contact end of pressure switch B.
a. If resistance is 300 ohms or less, stop engine, connect leads, and go to test 2.
b. If resistance is more than 300 ohms, replace low air pressure switch (para. 3-86).
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