TM 5-3805-254-20-1
ORGANIZATIONAL TROUBLESHOOTING - CONTINUED
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
64.
AIR PRESSURE DOES NOT EXCEED 90 PSI - CONTINUED.
Step 4. Check air compressor governor (1) for proper operation as follows: start engine (TM 5-3805-254-
10), wait for air compressor (2) to cut out approximately 120 psi, have assistant apply brake
pedal several times and note air pressure when air compressor (2) cuts in.
a.If air compressor (2) cuts in below 80 psi, notify Direct Support Maintenance.
b.If air compressor governor (1) discharges air pressure out of exhaust port (3) before
the air system reaches 120 psi, notify Direct Support Maintenance.
c. If air compressor (2) cuts in at 80 psi, go to step 5.
d.If air compressor governor (1) discharges air pressure out of exhaust port (3) when
the air system reaches 120 psi, go to step 5.
Step 5. Check air hoses for leaks or damage as follows: listen for hissing noise along air hoses.
a.If leaks are found, or air hoses are damaged, replace (page 2-947).
b.If leaks are not found, or air hoses are not damaged, go to step 6.
Step 6. Check front and rear relay valves (4 and 5) for leaks or damage as follows: have assistant press
brake pedal (6) down and hold it. Listen for hissing noise on or around front and rear relay
valves (4 and 5). Release brake pedal (6).
a.If front or rear relay valves (4 and 5) are leaking or damaged, replace, notify Direct
Support Maintenance.
b.If front or rear relay valves (4 and 5) are not leaking or damaged, go to step 7.
NOTE
Check AIR PRESSURE gage for air pressure between 90 and 130 psi. If specified air pressure is
not present, start engine and check that air pressure in air system is between 90 and 130 psi (TM
5-3805-254-20). Shut down engine (TM 5-3805-254-20).
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