HOSE 1064572 - Caterpillar

Solenoids
The solenoid valves are an output of the ECM. The ECM uses a pulse width modulated signal (PWM) in order to vary the current to the solenoid. The travel distance of the piston is proportional to the electrical current. The position of the valve opens or the position of the valve blocks the flow of oil to the hydraulic cylinder.Shift Solenoids
Illustration 1 g01316666When a clutch solenoid is shorted to ground or the circuit is open, all of the gears that use that clutch are not available. If a clutch solenoid is shorted to the +battery, only the gears that are associated with that clutch are available. If more than one clutch is shorted to the +battery, the control cannot function and the transmission shifts to no clutch NEUTRAL until the problem is fixed. When a clutch solenoid has failed, the lockup clutch is turned OFF.The software for the ECM keeps a list of available gears when a diagnostic code occurs. The transmission can select NEUTRAL and the shifter can still be in gear. Use the shift lever in order to select NEUTRAL. Use the shift lever to select a gear. When a diagnostic code occurs, if the current gear is available, the control will remain in that gear. But, if the diagnostic code is present on an active clutch, the software determines the appropriate desired gear. When a diagnostic code is active, the default logic will pick the next available lower gear as long as the output speed does not exceed the maximum output speed allowed for that gear. If a lower gear is not available or the output speed is too high for that gear, select the next higher gear available. The solenoids have a connector with two contacts. The solenoid receives +battery voltage from the ECM through contact 1. The solenoid receives ground from the ECM through contact 2.The ECM records the following diagnostic codes for the shift solenoids:
CID 1401
CID 1402
CID 1403
CID 1404
CID 1405
CID 1406Lockup Clutch Solenoid
Illustration 2 g01316666The lockup solenoid electrically controls the direct drive function. The ECM activates the lockup solenoid with +battery voltage and the lockup solenoid is deactivated when +battery voltage is not present. The lockup solenoid controls the flow of the oil to the lockup clutch valve. Direct drive is used in the upper transmission speeds. the lockup solenoid is activated when the machine is in direct drive. Torque converter drive is used in the lower transmission speeds. the lockup solenoid is deactivated when the machine is using torque converter drive.The solenoid has a connector with two contacts. The solenoid receives +battery voltage from the ECM through connector contact J1-62. The solenoid receives ground from the ECM through connector contact J1-60.The ECM records diagnostic codes that occur with the lockup clutch solenoid as a CID 0709.Start Relay
Illustration 3 g01191644The relay is a two contact component. The signal contact connects to the ECM at contact J2-7. The relay activates the starting motor. This relay is part of the neutral start function. See the Systems Operation,