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This illustration shows a hydraulic schematic of the Ride Control System. With the Ride
Control System ON and the lift control valve in HOLD, oil is blocked at both the rod and head
ends of the lift cylinders.
When the ride control switch is activated, a signal is sent to the Machine ECM. When the
ground speed activation threshhold is reached, the ECM sends a corresponding signal to the
ride control relay. The ride control relay energizes the ride control solenoids and the precharge
solenoid and oil from the head end of the lift cylinders flows through the left ride control
solenoid which connects the head end of the lift cylinders to the ride control accumulator. Oil
from the rod end of the lift cylinders is open to the tank through the right ride control solenoid.
The accumulator precharge solenoid isolates the accumulator from the charge pump oil.
With the Ride Control System OFF, the ride control solenoids are de-energized. Oil from the
rod end of the lift cylinders is blocked from flowing to the tank through the right ride control
solenoid. Charge oil flows through the precharge valve to charge the ride control accumulator.
When the ride control relay is energized by the Machine ECM, the relay sends an override
voltage signal to the self-level diverter solenoid regardless of the self-level switch position.
The self-level diverter solenoid decouples the lift and tilt cylinders while the Ride Control
System is active.
SERV1833-01 - 73 - Text Reference
07/08