RETAINER 1387772 - Caterpillar

Push down on the parking brake button in order to activate the parking brake. Note: The indicator light will be illuminated when the parking brake control is activated.
Depress the service brake pedal repeatedly until there is no brake oil pressure.
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View of the brake control valve which is located under the cab
(1) Setscrew
(2) Brake control valve
(3) Service brake accumulator charging pressure
(4) Low brake oil pressure switch
Connect tooling (B2) 34,450 kPa (5,000 psi) pressure sensor to pressure taps (3).
Observe both pressure gauges. Before you start the engine, the oil pressure must be 0 kPa (0 psi).
Clear all personnel from the machine and from the area around the machine.
Start the engine.
Set the engine speed dial at "10".
Lower the left console.
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Power mode control button located on the soft panel switch
Push down on the power mode control button in order to activate power mode. Note: The indicator light will be illuminated when power mode is activated.
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Automatic Engine Speed Control (AESC) as displayed on the programmable function key in the monitor.
Disable the automatic engine speed control through the monitor by pressing the programmable button.
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Joystick (front switch)
Disable the hydraulic modulation control, if equipped. Press the front switch on the right joystick in order to deactivate hydraulic modulation.
The air conditioning should be turned off for the following test. Test Procedure
Allow the oil pressure to increase to the cut out pressure. Check the pressure at pressure taps (3) when the pressure stops increasing. Note: Refer to Table 2 in this manual for the correct pressure.
After the brake accumulators have been completely charged and the correct cut out pressure has been obtained, stop the engine.
Turn the engine start switch to the ON position, but do not start the engine.
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Low brake oil pressure indicator as displayed in the monitor.
Apply the service brakes repeatedly. Pause for two seconds between applications. Count the number of applications while you observe the pressure gauge. Note: A minimum of one or two brake applications will decrease the brake accumulator oil pressure to 8,000 kPa (1,160 psi) and the monitor will display a "LOW BRAKE OIL ACCUMULATOR PRESSURE" warning.Note: A minimum of five brake applications is required before the brake accumulator oil pressure decreases to 4,500 kPa (653 psi). This decrease in pressure indicates the operational status of the indicator and of service brake oil pressure switch (4).
Continue to apply the service brakes. Pause for two seconds between brake applications. When the pressure drops off rapidly, this pressure drop off indicates the approximate nitrogen precharge pressure in the brake accumulators. Note: Refer to Table 2 in this manual for the correct pressure.
Determine the number of brake applications that were required before the sudden pressure drop in Step 5. This number should be more than five times.
If the cut out pressure is not within proper specifications, perform the "Adjustment Procedure" to adjust the cut out pressure.
If the nitrogen precharge pressure is not within the specification, refer to Special Instruction, REHS5464, "Accumulator Discharging and Charging Procedures" for the required tooling, and the