Back-up Control (Engine brake)

If the selector lever is shifted to 2 position while driving in D4 (O/D) or D3, great driving force is applied to the clutch inside the transmission. Clutch operating pressure (line pressure) must be increased to deal with this driving force.

Fig 1: Automatic Transaxle Control Mechanism Line Pressure Control Graph (Back-Up Control - Engine Brake)

Courtesy of NISSAN MOTOR CO., U.S.A.