Reducing torque converter clutch activity in an automatic transmission for a motor vehicle

A method for controlling operation of a torque converter clutch in an automatic transmission for a motor vehicle, comprising the steps of:

• maintain a count of converter clutch events;
• measuring in a counter decrement timer the length of a period that begins at a converter clutch event;
• determining whether a change has occurred during a recent interval from a condition in which a clutch-lock is desired to a condition in which no clutch-lock is desired;
• if said change has occurred, then incrementing said count;
• if said change has not occurred, then determining the length of a first predetermined period corresponding to current vehicle speed;
• if the current period measured in the counter decrement timer exceeds said first predetermined period, then decrementing said count;
• if a delay period for clutch relock corresponding to the current count has expired, then enabling a lockup of the torque converter clutch to occur;
• and
• if said delay period has not expired, then preventing a relock of the torque converter clutch.