Transmission Clutch Solenoid Valves
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| Illustration 1 | g00483757 |
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| Illustration 2 | g00288432 |
The transmission clutch solenoid valves are outputs of the ECM. The purpose of the solenoid valves is to direct pilot oil to the ends of the control spool. The control spool will shift allowing pressure oil to the corresponding clutches. The ECM activates the appropriate transmission clutch solenoid valves by analyzing the current conditions. Three of the transmission clutch solenoid valves are for direction: 1, 2 and 3. Three of the transmission clutch solenoid valves are for speed: 4, 5 and 6. For movement of the machine, two transmission clutch solenoid valves are activated. One valve is for direction and one valve is for speed. When the transmission is in neutral, only transmission clutch solenoid valve 4 is activated.
Note: The neutral clutch is engaged two seconds after the operator selects neutral. During this delay, the transmission is in a "no clutch neutral" state. None of the transmission clutch solenoid valves are energized. This "no clutch neutral" state is provided in order to improve the quality of directional shifts. The ECM momentarily prevents the engagement of the neutral clutch as the operator changes from forward to reverse. The same event occurs during a shift from reverse to forward.
The transmission clutch solenoid valves have a connector with two contacts. One contact receives power from the corresponding connector contact of the ECM: J1-4, J1-10, J1-11, J1-17, J2-1 and J2-7. The other contact of all solenoid valves join together. The return wire goes to connector J1-7 and connector J2-3 of the ECM.
Differential Lock Solenoid Valve
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| Illustration 3 | g00483758 |
The differential lock solenoid valve is an output of the ECM. The differential lock solenoid is the on/off control of the differential lock control system. When the system is locked the solenoid is off. When the system is unlocked the solenoid is on. The differential lock solenoid has a connector with two contacts. One contact receives power from connector J2-13 of the ECM. The other contact returns to connector J1-7 and connector J2-3 of the ECM.
Lockup Clutch Solenoid Valve
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| Illustration 4 | g00329246 |
The lockup clutch solenoid valve is an output of the ECM and functions as a proportional valve. The lockup clutch solenoid valve activates the lockup (direct drive). The lockup function is activated when the ECM sends a high current signal to the solenoid valve. The lockup function is deactivated when the ECM does not send a current signal to the solenoid valve.
The lockup clutch solenoid valve is part of a valve body that is located on the torque converter. The solenoid valve has a connector with two contacts. Connector contact 1 of the solenoid valve receives power from connector contact J2-8 of the ECM. The wire from connector contact "2" of all solenoid valves join together. The return wire goes to connector contact J1-7 and J2-3 of the ECM.