Control systems for a variable capacity engine oil pump

A method of operating an oil circulating control system of an engine, the method comprising:

• determining a speed of the engine;
• receiving a first mode request signal;
• based on the speed of the engine, selecting a first pressure mode of an oil pump of the engine when the first mode request signal is in a first state;
• based on the speed of the engine, selecting a second pressure mode of the oil pump when the mode request signal is in a second state;
• signaling a solenoid valve of a variable oil pressure circuit of the oil pump to transition to a first position when operating in the first pressure mode and to a second position when operating in the second pressure mode;
• generating a second mode request signal based on the speed of the engine, an oil pressure of the engine, and an oil temperature of the engine;
• and
• signaling the solenoid valve based on the second mode request signal,
• wherein
• the second mode request signal indicates a request for the first pressure mode when the oil pressure of the engine decreases to a first oil pressure that is less than a predetermined threshold, and
• the second mode request signal indicates a request for the second pressure mode when the oil pressure of the engine increases to a second oil pressure that is greater than the first oil pressure.

An oil circulating control system for an engine comprising:

• an engine speed module that determines a speed of the engine;
• a mode selection module that is configured to, based on the speed of the engine, select a first pressure mode and a second pressure mode of an oil pump of the engine, wherein the selection module selects one of the first pressure mode and the second pressure mode based on at least one mode request signal,
• wherein the mode selection module signals a solenoid valve of a variable oil pressure circuit of the oil pump to transition to a first position when operating in the first pressure mode and to a second position when operating in the second pressure mode;
• and
• at least one of
• an activation time module that generates a first mode request signal based an oil temperature of the engine and an amount of time that the variable oil pressure circuit is operating in the second pressure mode,
• a solenoid voltage module that generates a second mode request signal based on voltage of the solenoid valve,
• an engine run time module that generates a third mode request signal based on an engine run time and an oil temperature of the engine, and
• a diagnostic module that generates a fourth mode request signal based on a diagnostic fault,
• wherein the at least one mode request signal includes at least one of the first mode request signal, the second mode request signal, the third mode request signal, and the fourth mode request signal.