TM 5-3805-260-24
6. Disassemble the control valve and check for worn or
damaged parts.
7. If this does not correct the problem, install a new
valve.
Emergency Brake Control Valve
1. Start the engine and let the pressure go up to cutout
pressure [125 + 5 psi (860 + 35 kPa)].
2. With the control knob for the emergency brake in the
OFF position (pushed in), stop the engine.
3. Hold the control knob for the parking brake in the OFF
position (pushed in). Push the brake pedal rapidly
several times, until the control knob automatically
moves to the ON position.
4. Read the pressure on the gauge.
5. The correct pressure to automatically engage the
emergency brakes is 40 + 5 psi (280 + 35 kPa). If the
pressure on the gauge is not correct. the operation of
the control valve is not correct.
6. Disassemble the control valve and check for worn or
damaged parts.
7. If this does not correct the problem, install a new
valve.
Electric Warning System
1. Turn on the disconnect switch.
2. Start the engine.
3. Let the pressure go up to governor cutout pressure
[125 + 5 psi (860 + 35 kPa)].
4. Slowly let the air out by pushing on the brake pedal.
Note the air pressure shown on the gauge at which
warning buzzer (3) begins. This must be at
approximately 60 psi (415 kPa).
5. If warning buzzer (3) does not begin to sound at
approximately 60 psi (415 kPa), check the electrical
connections for pressure indicator (5) and warning
buzzer (3).
6.
If the connections are good, connect a continuity
light across the terminals of one of the indicator and
buzzer.
ELECTRIC WARNING SYSTEM
1. Pin connector. 2. Ammeter. 3. Low air pressure
warning buzzer. 4. Circuit breaker. 5. Low air
pressure indicator. 6. Starter switch.
7. If the continuity light does not operate, install a new
pressure indicator warning buzzer.
8. If low pressure buzzer (3) comes ON above
approximately 65 psi (450 kPa), stop the engine.
9. Install a new pressure indicator.
10.Start the engine.
11 Let the pressure go up to cutout pressure.
12.Slowly open the center tank drain valve.
13.Warning buzzer (3) must come ON at approxi-mately
60 psi (415 kPa).
2-149
