PUMP GP-GEAR 6Y0484 - Caterpillar

Illustration 1 g06243536
Parking brake circuit
The components of the parking brake circuit are the parking brake switch, the transmission oil pressure sensor, the parking brake solenoids, the Power Train Electronic Control Module (Power Train ECM), the Caterpillar Monitoring System ECM, the parking brake oil pressure sensor, the low parking brake oil pressure sensor, and the brake accumulator oil pressure switch for brake application.
Illustration 2 g03392281
Dash panel
(1) Parking brake switch
Illustration 3 g01145171
Rear view of transmission
(2) Transmission oil pressure sensor
Illustration 4 g06215057
View of transmission compartment
(3) Parking brake dump solenoid
(4) Parking brake supply solenoid
Illustration 5 g01145175
Cab
(5) Power Train Electronic Control Module (ECM)With the key start switch in the ON position, 24 V power is supplied from the batteries to circuit breaker 8 and circuit breaker 10. Circuit breaker 8 supplies 24 V power to the Power Train ECM. Circuit breaker 10 supplies 24 V power to the Caterpillar Monitoring System ECM, and the transmission oil pressure sensor.
Illustration 6 g03392284
Dash panel
(6) Caterpillar Monitoring System ECM (behind display)
(7) Parking brake alert indicator
Illustration 7 g06215060
View of transmission bay
(8) Brake accumulator oil pressure switch for brake application
Illustration 8 g06215061
View of parking brake control valve
(9) Parking brake oil pressure switchWhen parking brake switch (1) is moved to the ON position, 24 V power to parking brake supply solenoid (4) is interrupted. 24 V power is supplied to parking brake dump solenoid (4). The pressure oil in the wheel brakes is returned to the hydraulic tank and the parking brake is engaged. In this condition, parking brake oil pressure switch (9) sends a signal to the Power Train ECM. The Power Train ECM sends a signal via the CAT Data Link to Caterpillar Monitoring System ECM (6). Caterpillar Monitoring System ECM (6) turns on parking brake alert indicator (7).When the key start switch is in the ON position and the parking brake switch is in the OFF position, the parking brake switch must be cycled to allow the parking brake to be disengaged.When the oil pressure decreases in the brake system, brake accumulator oil pressure switch for brake application (8) will activate. The brake accumulator oil pressure switch then sends a signal to the Power Train ECM to engage the parking brake.When the oil pressure in the transmission decreases below a set value, transmission oil pressure sensor (2) sends a signal to the Power Train ECM. The Power Train ECM illuminates the low transmission oil pressure indicator and engages the parking brake.When the parking brake switch is moved to the OFF position, power from the Power Train ECM is supplied to energize the parking supply solenoid. Energizing the parking brake supply solenoid will allow pressure oil to flow to the wheel brakes to disengage the parking brake. The parking brake alert indicator will be off.
Illustration 9 g03339038
Indicator lamp panel
(10) Parking brake oil pressure alert indicator
Illustration 10 g06215062
View of parking brake control valve
(11) Parking brake oil pressure sensorWhen parking brake switch (1) is moved to the OFF position, 24 V power is supplied to parking brake supply solenoid (4). The parking brakes will be released. Parking brake oil pressure