Modulating Pressure Switchover Design/Task/Function

Task
Protecting the selector elements of the automatic transmission from excessive thermal stresses during power shifts when the cruise control is operated.

Function
When the cruise control is operating, the injected quantity is controlled directly by the IFI control module (N3/7) or the DFI control module (N3/8).
The AT/CC modulating pressure switchover valve (Y3/4) and the AT/CC upshift retard shiftover valve (Y3/5) are installed to protect the transmission and for power downshifts. The switchover valves are actuated by the IFI control module (N3/7) or DFI control module (N3/8) when the cruise control is operated. This is necessary as the accelerator pedal position sensor (R25/2) as well as the vacuum control valve (65) are in the closed throttle position when the cruise control is operating.