TM 9-2320-272-24-1
Table 2-4. Compressed Air and Brake System Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
14. SECONDARY PRESSURE GAUGE READS NO PRESSURE, LOW PRESSURE, OR BUILDS TO NORMAL
OPERATING PRESSURE SLOWLY. PRIMARY PRESSURE GAUGE READS NORMAL (ENGINE IDLING, BRAKE
PEDAL NOT APPLIED)
Test 1. Perform malfunction 13, test 1.
Test 2. Check secondary air pressure gauge (3).
Step 1. Stop engine and open all drainvalves (1), in sequence shown, until brake system air
pressure is vented.
Step 2. Close drainvalves (1).
Step 3. Disconnect air line (2) from secondary air pressure gauge (3).
Step 4. Connect test gauge to air line (2).
Step 5. Direct assistant to start engine and allow air system to build to normal operating
pressure.
Step 6. Check test gauge reading.
a. If test gauge reads normal operating pressure, replace secondary air pressure
gauge (3) (para. 3-87).
b. If test gauge reads no pressure, low pressure, or pressure is building slowly, perform
test 3.
c. Stop engine, drain air, remove test gauge, and connect air line (2).
DRAINVALVE SEQUENCE
2-206
