Vehicle brake system and diagnostic method for determining a leak in a simulator valve
AssigneeZF Active Safety US Inc.
InventorBlaise Ganzel
Life of this patent
Estimating the term…
Abstract
A diagnostic method to identify a leak in a simulator valve for a vehicle brake system comprising the steps of: (1) energizing a secondary three-way valve, a pumping valve, a simulator test valve, and a plurality of apply valves in order to maintain a pressure medium from a plunger assembly within a boost circuit; (2) applying a plunger in the plunger assembly to a predetermined pressure level; (3) holding the plunger in position within the plunger assembly; and (4) identifying a leak in a simulator valve via a signal from an ECU to a vehicle user interface if the pressure in the boost circuit deteriorates at or more than a pre-determined rate.
Claims16
A diagnostic method to identify a leak in a simulator valve for a vehicle brake system comprising the steps of:
- energizing a secondary three-way valve, a pumping valve, a simulator test valve, and a plurality of apply valves in order to maintain a pressure medium from a plunger assembly within a boost circuit;
- applying a plunger in the plunger assembly to a predetermined pressure level;
- holding the plunger in position within the plunger assembly;
- and
- identifying a leak in a simulator valve via a signal from an ECU to a vehicle user interface if the pressure in the boost circuit deteriorates at or more than a pre-determined rate.
A diagnostic method to identify a leak in a simulator valve for a vehicle brake system comprising the steps of:
- energizing a secondary three-way valve, a pumping valve, a simulator test valve, and a plurality of apply valves in order to maintain a medium from a plunger assembly within a boost circuit;
- applying pressure to the boost circuit via a plunger in the plunger assembly to achieve a predetermined pressure level in the boost circuit;
- holding the plunger in position and measuring the pressure in the boost circuit;
- measuring a rate of pressure deterioration in the boost circuit;
- and
- comparing the rate of pressure deterioration against a predetermined value;
- and
- identifying a leak in the simulator valve via a signal from an ECU to a vehicle user interface if the plunger traveled more than a pre-determined distance within the plunger assembly when achieving the predetermined pressure level in the boost circuit.
Dependencies are inferred from the claim text.