Suspension leak check systems and methods

1. A leak checking system for a suspension system of a vehicle, the leak checking system comprising:

a state module configured to selectively set a present state of a leak check for the suspension system to a first state;

a valve control module configured to determine first target open and closed states for valves of the suspension system based on the present state being set to the first state and to open and close the valves of the suspension system according to the first target open and closed states, respectively;

a pump control module configured to, when the valves are in the first target open and closed states, respectively, selectively operate an electric pump of the suspension system in a first direction to increase hydraulic fluid pressure in a first portion of the suspension system;

a leak module configured to selectively diagnose a leak in a first one of the valves associated with the first state based on a first pressure in the first portion of the suspension system while the valves are open and closed according to the first target open and closed states for the first state;

wherein:

the state module is further configured to selectively set the present state of the leak check for the suspension system to a second state;

the valve control module is further configured to determine second target open and closed states for the valves of the suspension system based on the present state being set to the second state and to open and close the valves of the suspension system according to the second target open and closed states, respectively,

the second target open and closed states are different than the first target open and closed states;

the pump control module is further configured to, when the valves are in the second target open and closed states, respectively, selectively operate the electric pump of the suspension system in the first direction to increase hydraulic fluid pressure in a second portion of the suspension system;

the leak module selectively diagnose a leak in a second one of the valves associated with the second state based on a second pressure in the second portion of the suspension system while the valves are open and closed according to the second target open and closed states for the second state; and

the second portion is different the first portion.

2. The leak checking system of claim 1 wherein the state module is configured to receive a start signal via an on board diagnostic port of the vehicle and to set the present state of the leak check to the first state in response to receipt of the start signal.

3. The leak checking system of claim 2 further comprising a service module configured to generate the start signal in response to receipt of user input to the service module.

4. The leak checking system of claim 1 wherein the target state of the first one of the valves is closed during the first state.

5. The leak checking system of claim 1 wherein the leak module is configured to diagnose a leak in the first one of the valves associated with the first state when the first pressure in the first portion of the suspension system does not become greater than a first predetermined pressure within a first predetermined period of beginning to operate of the electric pump in the first direction while the valves are open and closed according to the first target open and closed states.

6. The leak checking system of claim 5 wherein the leak module is configured to diagnose a leak in the first one of the valves associated with the first state when the first pressure in the first portion of the suspension system becomes less than a second predetermined pressure after becoming greater than or equal to the first predetermined pressure,

wherein the second predetermined pressure is less than the first predetermined pressure.

7. The leak checking system of claim 6 wherein the leak module is configured to diagnose that no leak is present in the first one of the valves associated with the first state when:

the first pressure in the first portion of the suspension system becomes greater than the first predetermined pressure within the first predetermined period of beginning to operate of the electric pump in the first direction while the valves are open and closed according to the first target open and closed states; and

does not become less than the second predetermined pressure after becoming greater than or equal to the first predetermined pressure.

8. The leak checking system of claim 1 wherein:

the state module is further configured to selectively set the present state of the leak check for the suspension system to a third state;

the valve control module is further configured to determine third target open and closed states for the valves of the suspension system based on the present state being set to the third state and to open and close the valves of the suspension system according to the third target open and closed states, respectively;

the pump control module is further configured to, when the valves are in the third target open and closed states, respectively, selectively operate the electric pump of the suspension system in the first direction to increase hydraulic fluid pressure in a third portion of the suspension system; and

the leak module selectively diagnose a leak in a third one of the valves associated with the third state based on a third pressure in the third portion of the suspension system while the valves are open and closed according to the third target open and closed states for the third state.

9. The leak checking system of claim 1 wherein the leak module is configured to diagnose a leak in the second one of the valves associated with the second state when the second pressure in the second portion of the suspension system does not become greater than a first predetermined pressure within a first predetermined period of beginning to operate of the electric pump in the first direction while the valves are open and closed according to the second target open and closed states.

10. The leak checking system of claim 9 wherein the leak module is configured to diagnose a leak in the second one of the valves associated with the second state when the second pressure in the second portion of the suspension system becomes less than a second predetermined pressure after becoming greater than or equal to the first predetermined pressure,

wherein the second predetermined pressure is less than the first predetermined pressure.

11. A leak checking method for a suspension system of a vehicle, the leak checking method comprising:

selectively setting a present state of a leak check for the suspension system to a first state;

determining first target open and closed states for valves of the suspension system based on the present state being set to the first state;

selectively opening and closing the valves of the suspension system according to the first target open and closed states, respectively;

when the valves are in the first target open and closed states, respectively, selectively operating an electric pump of the suspension system in a first direction to increase hydraulic fluid pressure in a first portion of the suspension system;

selectively diagnosing a leak in a first one of the valves associated with the first state based on a first pressure in the first portion of the suspension system while the valves are open and closed according to the first target open and closed states for the first state;

selectively setting the present state of the leak check for the suspension system to a second state;

determining second target open and closed states for the valves of the suspension system based on the present state being set to the second state and to open and close the valves of the suspension system according to the second target open and closed states, respectively,

wherein the second target open and closed states are different than the first target open and closed states;

when the valves are in the second target open and closed states, respectively, selectively operating the electric pump of the suspension system in the first direction to increase hydraulic fluid pressure in a second portion of the suspension system; and

selectively diagnosing a leak in a second one of the valves associated with the second state based on a second pressure in the second portion of the suspension system while the valves are open and closed according to the second target open and closed states for the second state,

wherein the second portion is different the first portion.

12. The leak checking method of claim 11 further comprising:

receiving a start signal via an on board diagnostic port of the vehicle; and

setting the present state of the leak check to the first state in response to receipt of the start signal.

13. The leak checking method of claim 12 further comprising receiving the start signal from a service module that is external to the vehicle and that is configured to generate the start signal in response to receipt of user input to the service module.

14. The leak checking method of claim 11 wherein the target state of the first one of the valves is closed during the first state.

15. The leak checking method of claim 11 wherein selectively diagnosing a leak includes diagnosing a leak in the first one of the valves associated with the first state when the first pressure in the first portion of the suspension system does not become greater than a first predetermined pressure within a first predetermined period of beginning to operate of the electric pump in the first direction while the valves are open and closed according to the first target open and closed states.

16. The leak checking method of claim 15 wherein selectively diagnosing a leak includes diagnosing a leak in the first one of the valves associated with the first state when the first pressure in the first portion of the suspension system becomes less than a second predetermined pressure after becoming greater than or equal to the first predetermined pressure,

wherein the second predetermined pressure is less than the first predetermined pressure.

17. The leak checking method of claim 16 wherein selectively diagnosing a leak includes diagnosing that no leak is present in the first one of the valves associated with the first state when:

the first pressure in the first portion of the suspension system becomes greater than the first predetermined pressure within the first predetermined period of beginning to operate of the electric pump in the first direction while the valves are open and closed according to the first target open and closed states; and

does not become less than the second predetermined pressure after becoming greater than or equal to the first predetermined pressure.

18. The leak checking method of claim 11 further comprising:

selectively setting the present state of the leak check for the suspension system to a third state;

determining third target open and closed states for the valves of the suspension system based on the present state being set to the third state;

selectively opening and closing the valves of the suspension system according to the third target open and closed states, respectively;

when the valves are in the third target open and closed states, respectively, selectively operating the electric pump of the suspension system in the first direction to increase hydraulic fluid pressure in a third portion of the suspension system; and

selectively diagnosing a leak in a third one of the valves associated with the third state based on a third pressure in the third portion of the suspension system while the valves are open and closed according to the third target open and closed states for the third state.