Table 3-1. Troubleshooting

TM 9-2320-273-10

Table 3-1. Troubleshooting

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

AIR SYSTEM AND BRAKES

AIR RESERVOIR PRESSURE LOW (WARNING LIGHT AND BUZZER ARE ON).

Step 1. Check that all air reservoir draincocks are closed.

Close all draincocks.

Step 2. If tractor is not coupled to a trailer, check that trailer air supply control

is pulled out (OFF).

Pull trailer air supply control out.

Step 3. Check for possible air leaks at air reservoirs, hoses, fittings, and at

inter vehicular air hose connections.

Notify Organizational Maintenance of any leaks.

Step 4. If tractor is coupled to semitrailer, and your tests and inspections of

truck do not reveal any trouble with truck air system, troubleshoot

semitrailer.

If your tests, inspections, and corrective actions for both

tractor and semitrailer do not solve the low air pressure

problem, notify Organizational Maintenance.

AIR SYSTEM LOSES PRESSURE DURING TRUCK OPERATION OR LOW AIR

PRESSURE WARNING LIGHT AND BUZZER COME ON DURING TRUCK

OPERATION.

Step 1. Make sure that trailer air supply control is pulled out, operate engine

until warning light and buzzer go off, and release parking brake. Stop

engine and note reservoir pressure. Fully depress and hold service brake

pedal for 2 minutes. Have crew member check for leaks, Reservoir

pressure loss during 2-minute period should not exceed 5 psi.

Close any open reservoir drains; make sure that trailer

air supply control is pulled out. if you find any other

leaks, notify Organizational Maintenance.

Step 2. If pressure loss in test above does not exceed 5 psi in 2 minutes, push

in trailer air supply control to charge semitrailer air reservoirs and

repeat the test procedure. Have crew member check semitrailer for leaks.

Pressure loss should not exceed 5 psi in 2 minutes.

Note any semitrailer air leaks. If reservoir pressure

loss exceeds 5 psi in 2 minutes, troubleshoot the semitrailer.

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