Method of diagnosing a vehicle engine cooling system

• US 6,829,530 B2
• Filed: 07/22/2003
• Issued: 12/07/2004
• Est. Priority Date: 07/23/2002
• Status: Expired due to Fees

• Current Assignee: C.R.F. Societa Consortile Per Azioni
• Original Assignee: C.R.F. Societa Consortile Per Azioni
• Inventors: Bianconi, Maria Paola, Mauro, Marco, Gambera, Mario, Fortunato, Andrea
• Primary Examiner(s): Vo, Hieu T.
• Application Number:
  US10/624,920
• Publication Number:
  US 20040129067A1
• Time in Patent Office: 504 Days
• Field of Search: 701/114, 701/102, 731/173, 731/181, 123/41.01, 123/41.15, 123/41.21, 123/41.27
• US Class Current: 701/114
• CPC Class Codes: F01P 11/14 Indicating devices; Other safety devices
• CPC Class Codes: F01P 11/16 concerning coolant temperature F01P11/20 takes precedence
• CPC Class Codes: F01P 2025/30 Engine incoming fluid temperature
• CPC Class Codes: F01P 2025/32 Engine outcoming fluid temperature
• CPC Class Codes: F01P 2025/36 Heat exchanger mixed fluid temperature
• CPC Class Codes: F01P 2025/52 Heat exchanger temperature
• CPC Class Codes: F01P 2031/20 Warning devices
• CPC Class Codes: F01P 2031/36 Failure of coolant pump
• CPC Class Codes: F01P 5/14 Safety means against, or active at, failure of coolant-pumps drives, e.g. shutting engine down; Means for indicating functioning of coolant pumps

Abstract

A method of diagnosing a cooling system of a vehicle engine, including the steps of: acquiring operating data relative to operation of the cooling system (cooling system radiator water temperature/fan rotation speed) during a trip time between turn-on of the engine and subsequent turn-off of the engine; processing the acquired data, and accumulating the data for each trip to create a database; and examining the location of the data within the database to determine malfunction and/or potential malfunction situations of the cooling system.

Claims

1. A method of diagnosing a cooling system of a vehicle engine, characterized by comprising the steps of:

acquiring operating data relative to operation of the cooling system between turn-on of the engine and subsequent turn-off of the engine;

processing the acquired operating data and accumulating the data to create at least one database; and

examining the location of the data within said database to determine malfunction and/or potential malfunction situations of said cooling system.

2. A method as claimed in claim 1, wherein said step of acquiring operating data relative to operation of the cooling system comprises the step of acquiring fluid temperatures of a radiator of said cooling system.

3. A method as claimed in claim 2, wherein said acquiring step comprises the step of acquiring the temperature of the fluid supplied to the inlet and outlet of said radiator.

4. A method as claimed in claim 3, and comprising the step of calculating the temperature difference between the fluid supplied to the inlet and outlet of said radiator.

5. A method as claimed in claim 4, wherein said accumulating step comprises the step of forming a data structure in which are stored a number of operating states, each defined as a function of the calculated temperature difference value and the acquired outlet fluid temperature value.

6. A method as claimed in claim 4, wherein said accumulating step comprises the step of forming a data structure in which are stored a number of operating states, each defined as a function of the calculated temperature difference value and the acquired inlet fluid temperature value.

7. A method as claimed in claim 1, wherein said step of acquiring operating data relative to operation of the cooling system comprises the step of acquiring the rotation speed of a fan associated with a radiator of said cooling system.

8. A method as claimed in claim 7, wherein said step of processing the acquired operating data comprises the steps of:

calculating the mean value of said rotation speed; and

calculating the variance of said rotation speed.

9. A method as claimed in claim 8, wherein said accumulating step comprises the step of forming a data structure storing the mean value of the rotation speed values acquired between turn-on and subsequent turn-off of said engine.

10. A method as claimed in claim 8, wherein said accumulating step comprises the step of forming a data structure storing the variance of the rotation speed values acquired between turn-on and subsequent turn-off of said engine.

11. A method as claimed in claim 1, wherein said step of examining the location of the data within said database comprises the steps of:

defining different areas within said database, corresponding to different operating states of said cooling system; and

checking the location of said data within said areas.

12. A method as claimed in claim 11, wherein said step of examining the location of the data within said database comprises the step of determining when a maximum time value associated with an acquired operating state located in a danger area is exceeded.

13. A method as claimed in claim 11, wherein said step of examining the location of the data within said database comprises the step of determining migration of said operating states towards a danger area.