Electro-hydraulic control system diagnostics
AssigneeAllison Transmission, Inc.
InventorCharles F. Long
Life of this patent
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Abstract
Various embodiments of methods, apparatus and systems that diagnose and/or detect faults of an electro-hydraulic control system for a transmission are presented. Some embodiments, adjust a main line pressure of the electro-hydraulic control system and detect faults based upon changes in a pressure switch resulting from such adjustments of the main line pressure. The pressure switch may be incorporated into a control main valve or a clutch trim valve of the electro-hydraulic control system.
Claims17
An electro-hydraulic control system for a transmission, the electro-hydraulic control system comprising:
- an electronic control module configured to (i) generate control signals to increase a main line pressure of the electro-hydraulic control system from a nominal level to a first pressure level and control signals to increase the main line pressure from the first pressure level to a second pressure level, (ii) receive a status signal indicative of a status of a pressure switch of the electro-hydraulic control system at the first pressure level or the second pressure level, and (iii) detect a fault as a function of a lack of change in the status of the pressure switch at the first pressure level or the second pressure level.
An electro-hydraulic control system for a transmission, the electro-hydraulic control system comprising:
- an electronic control module configured to (i) generate control signals to increase a main line pressure of the electro-hydraulic control system from a nominal level to a first pressure level and control signals to increase the main line pressure from the first pressure level to a second pressure level, (ii) receive a status signal indicative of a status of a pressure switch of the electro-hydraulic control system at each of the first pressure level and the nominal pressure level, and (iii) detect a fault as a function of a lack of change in the status of the pressure switch at the first pressure level or the nominal pressure level.
Dependencies are inferred from the claim text.