Which statement about programmed vs modulated lock-up strategies is correct?

Which statement about programmed vs modulated lock-up strategies is correct?

• A. Technician A
• B. Technician B
• C. Both Technician A and Technician B
• D. Neither Technician A nor Technician B

Answer: (A)

Lock-up strategies decide how the torque converter clutch is controlled to balance efficiency and drivability. A programmed lock-up approach uses a fixed map of when to engage or disengage the clutch based on speed and load, so at cruising conditions the clutch locks in place to minimize slip and improve fuel economy, with disengagement occurring under conditions that protect shifting quality or torque handling. A modulated lock-up approach, by contrast, uses a control signal to vary the amount of slip continuously, smoothing torque transfer as conditions change and preventing abrupt transitions. Technician A’s statement aligns with this distinction: the programmed method follows predefined points for lock-up, while the modulated method adjusts engagement more fluidly to match driving demands. The other possibilities would misstate the relationship between control method and slip behavior, either treating both strategies as the same or implying fixed slip in a way that defeats the purpose of modulation.

Lock-up strategies decide how the torque converter clutch is controlled to balance efficiency and drivability. A programmed lock-up approach uses a fixed map of when to engage or disengage the clutch based on speed and load, so at cruising conditions the clutch locks in place to minimize slip and improve fuel economy, with disengagement occurring under conditions that protect shifting quality or torque handling. A modulated lock-up approach, by contrast, uses a control signal to vary the amount of slip continuously, smoothing torque transfer as conditions change and preventing abrupt transitions.

Technician A’s statement aligns with this distinction: the programmed method follows predefined points for lock-up, while the modulated method adjusts engagement more fluidly to match driving demands. The other possibilities would misstate the relationship between control method and slip behavior, either treating both strategies as the same or implying fixed slip in a way that defeats the purpose of modulation.