HARNESS AS-ENGINE 1976901 - Caterpillar

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Main control valve
(3) Main relief valve
Loosen the locknut on main relief valve (3).
Turn the adjustment screw on main relief valve (3) clockwise until the pressure at the load sensing signal pressure tap has decreased to the correct pressure. Refer to Table 1 for the correct pressure.Note: A quarter turn of the adjustment screw clockwise to increase the pressure approximately 4,000 kPa (580 psi).
While the adjustment screw on main relief valve (3) is being held, tighten the locknut to the specified torque.Test Procedure
To prevent injury or death, never work under a machine while a test is being performed.
Clear all personnel from the machine and from the area around the machine.
Start the engine.
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Power mode control button on the soft panel switch
Push down on the power mode control button 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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Hydraulic modulation switch on left joystick
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Hydraulic modulation aggressive mode (monitor display)
Select the hydraulic modulation mode as aggressive. Press the lower front switch on the left joystick to select the hydraulic modulation mode.
The air conditioning should be turned off for the following test.
Clear all personnel from the machine and from the area around the machine.
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Engine speed dial
Set the engine speed dial at "1".Note: Do not activate any implements.
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Transmission control button on the soft panel switch
Push down on the transmission control button to select SECOND GEAR.Note: The first indicator light will illuminate when the transmission is in SECOND GEAR.
Override the "Travel Pilot Solenoid Current Override" in the step sequence below to perform the test procedure.
Start Electronic Technician.
Select the "Machine ECM" from the list of available controls.
From the top menu, select "Diagnostics".
From the pull-down menu, select "Diagnostic Tests".
Then select "Override Parameters".
Select "Travel Motor Swashplate Angle Limit Solenoid Current Override" and adjust the current to 0.9 amp.
Select "Travel Forward Select Solenoid Override" and turn the solenoid to ON.
Select "Travel Pilot Solenoid Current Override" and adjust the current to 0.9 amp.
Lower the left console.
Release the service brake pedal.Note: Do not activate any implements.
Depress the travel speed pedal fully in the FORWARD position.
Slowly turn the adjustment screw on main relief valve (3) counterclockwise until the upstroke pressure at pressure tap (1) is within specifications. Refer to Table 1 for the correct pressure.
Deactivate the backup mode in the monitor.
Fully depress the service brake pedal until the service brake pedal locks mechanically.
Stop the engine.
Raise the left console.
If the upstroke pressure is not set to the proper specification, perform the"Adjustment Procedure"to adjust the upstroke pressure.Adjustment Procedure
Note: If the original cap is on the upstroke pressure adjustment screw, do not make adjustments until the root cause of failure has been verified.
Personal injury or death can result from sudden machine movement.Sudden movement of the machine can cause injury to persons on or near the machine.To prevent injury or death, make sure that the area around