Variable bleed solenoid recovery system

• US 20080120516A1
• Filed: 01/26/2007
• Published: 05/22/2008
• Est. Priority Date: 11/17/2006
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Thor, Todd J.
• Granted Patent: US 8,086,380 B2
• Time in Patent Office: Days
• US Class Current: 714/2
• CPC Class Codes: G06F 11/0739 in a data processing system embedded in automotive or aircraft systems
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40

Abstract

A recovery control system and method for automatic transmissions includes a diagnostic module that determines a fault condition of a variable bleed solenoid (VBS) when the automatic transmission fails to establish a desired drive ratio. A recovery module initiates a recovery cycle of the VBS based on the fault condition. The fault condition includes one of a clutch stuck-on condition and a clutch stuck-off condition. A clutch controlled by the VBS fails to disengage during the clutch stuck-on condition, and the clutch fails to engage during the clutch stuck-on condition.

Claims

1. A recovery control system for automatic transmissions, comprising:

a diagnostic module that determines a fault condition of a variable bleed solenoid (VBS) when the automatic transmission fails to establish a desired drive ratio; and

a recovery module that initiates a recovery cycle of said VBS based on said fault condition.

2. The system of claim 1 wherein said fault condition includes one of a clutch stuck-on condition and a clutch stuck-off condition, a clutch controlled by said VBS fails to disengage during said clutch stuck-on condition, and said clutch fails to engage during said clutch stuck-on condition.

3. The system of claim 2 wherein said diagnostic module increments one of a first count value and a second count value associated with said VBS when said diagnostic module detects one of said stuck-on condition and said stuck-off condition, respectively.

4. The system of claim 3 wherein said recovery module initiates said recovery cycle when said diagnostic module increments one of said first count value and said second count value.

5. The system of claim 3 wherein said diagnostic module stores a first threshold and a second threshold associated with said stuck-on condition and said stuck-off condition, respectively, and said diagnostic module activates a fault indicator when one of said first count value and said second count value exceeds one of said first threshold or said second threshold, respectively.

6. The system of claim 5 wherein said recovery module continues to execute said recovery cycle when said diagnostic module activates said fault indicator.

7. A recovery control method for automatic transmissions, comprising:

determining a fault condition of a variable bleed solenoid (VBS) when the automatic transmission fails to establish a desired drive ratio; and

initiating a recovery cycle of said VBS based on said fault condition.

8. The method of claim 7 wherein said fault condition includes one of a clutch stuck-on condition and a clutch stuck-off condition, a clutch controlled by said VBS fails to disengage during said clutch stuck-on condition, and said clutch fails to engage during said clutch stuck-on condition.

9. The method of claim 8 further comprising incrementing one of a first count value and a second count value associated with said VBS based on detecting one of said stuck-on condition and said stuck-off condition, respectively.

10. The method of claim 9 further comprising initiating said recovery cycle based on incrementing one of said first count value and said second count value.

11. The method of claim 9 further comprising storing a first threshold and a second threshold associated with said VBS and activating a fault indicator when one of said first count value and said second count value exceeds one of said first threshold and said second threshold, respectively.

12. The method of claim 11 further comprising continuing to execute said recovery cycle when said fault indicator is activated.

13. A recovery control system for a variable bleed solenoid (VBS) for an automatic transmission, comprising:

a recovery module that initiates a recovery cycle of said VBS when one of a first value and a second value that correspond to a clutch stuck-on condition or a clutch stuck-off condition, respectively, is detected; and

a diagnostic module that activates a fault indicator when one of said first value and said second value exceeds one of a first threshold and a second threshold, respectively,

wherein a clutch controlled by said VBS fails to disengage during said clutch stuck-on condition and said clutch fails to engage during said clutch stuck-on condition.

14. The system of claim 13 wherein said diagnostic module increments one of said first value and said second value associated with said VBS when said diagnostic module detects one of said stuck-on condition and said stuck-off condition, respectively.

15. The system of claim 13 wherein said recovery module initiates said recovery cycle when said diagnostic module increments one of said first value and said second value.

16. The system of claim 13 wherein said recovery module continues to execute said recovery cycle when said diagnostic module activates said fault indicator.