Vehicle hydraulic system monitoring system and method

In a vehicle hydraulic system having a hydraulic pump for supplying pressurized hydraulic fluid to a plurality of hydraulic function elements via a corresponding plurality of hydraulic element control valves, and for supplying lube fluid to a lubrication circuit, a method for monitoring and protecting the vehicle hydraulic system, the method comprising:

• sensing a lube pressure of lube fluid in the lubrication circuit;
• comparing the sensed lube pressure to a threshold;
• if the sensed lube pressure is less than the threshold, performing an operation on each hydraulic function element one after another;
• after each hydraulic function element is operated, comparing the sensed lube pressure to the threshold;
• and
• if the sensed lube pressure is not less than the threshold, deactivating the activated hydraulic function element and generating a corresponding message.

In a vehicle hydraulic system having a hydraulic pump for supplying pressurized hydraulic fluid to a plurality of hydraulic function elements via a corresponding plurality of hydraulic element control valves, and for supplying lube fluid to a lubrication circuit, a method for monitoring and protecting the vehicle hydraulic system, the method comprising:

• sensing a lube pressure of lube fluid in the lubrication circuit;
• comparing the sensed lube pressure to a threshold;
• if the sensed lube pressure is less than the threshold for a certain time period, performing an operation on each hydraulic function element one after another;
• after each hydraulic function element is operated, comparing the sensed lube pressure to the threshold;
• and
• if, as a result of said operation being performed on one of the hydraulic functions, the sensed lube pressure is not less than the threshold for said certain time period, deactivating said one hydraulic function element and generating a corresponding message.

In a vehicle hydraulic system having a plurality of hydraulic function elements, a hydraulic pump for supplying pressurized hydraulic fluid to the plurality of hydraulic function elements via a corresponding plurality of hydraulic element control valves, an electronic control unit (ECU) for controlling the element control valves, the pump also supplying lube fluid to a lubrication circuit, a method for monitoring the vehicle hydraulic system, the method comprising:

• sensing a lube pressure of lube fluid in the lubrication circuit;
• comparing the sensed lube pressure to a threshold;
• if the sensed lube pressure is less than the threshold for a certain time period, performing an operation on each hydraulic function element one after another;
• after each hydraulic function element is operated, comparing the sensed lube pressure to the threshold;
• and
• if, as a result of said operation being performed on one of the hydraulic functions, the sensed lube pressure is not less than the threshold for said certain time period, deactivating said one hydraulic function element and generating a corresponding message.