THEORY OF OPERATION - CONTINUED
ELECTRO-HYDRAULIC SYSTEM - CONTINUED
N OT E
Never activate solenoids with voltage or a signal that does not originate from the ECM or coils will be damaged.
General. These valves are pilot proportioning solenoid valves:
Raise Solenoid Valve
Lower Solenoid Valve
Dump Solenoid Valve
Tilt Back Solenoid Valve
Auxiliary or Third Function Solenoid Valves
Pilot Proportioning Solenoid Valve.
Pilot proportioning solenoid valves are implement ECM outputs which direct a proportional amount of
pilot oil to main control valve. Stems in main control valve shift to allow pump supply oil to corresponding
cylinder. When an operator moves joystick control, implement ECM activates appropriate solenoid valve.
Solenoid valves are energized with a PWM signal sent by implement ECM. PWM signal acts as a source
of variable current to activate solenoid.
Solenoid valves have a connector with two contacts. One contact receives input from corresponding imple-
ment ECM contact (J1-48, J1-49, J1-51, J1-52, J1-58, and J1-59). Output returns for solenoid valves are
contacts J1-50 and J1-60 of implement ECM (see Table 9).