1 Position (Deceleration)

The power flow in 1 when decelerating is as follows:

• Hydraulic pressure is applied to the 1st clutch and the 1st-hold clutch.
• Rolling resistance from the road surface goes through the front wheels to the final driven gear, then to the countershaft 1st gear.
• The one-way clutch cannot transmit the power from the countershaft 1st gear because the application of torque is reversed.
• The countershaft 1st gear drives the secondary shaft 1st gear, which in turn drives the secondary shaft via the 1st-hold clutch.
• The force transmitted to the secondary shaft idler gear turns the mainshaft 3rd gear via the countershaft idler gear. As a result, engine braking can be obtained with 1st gear.
  Fig 1: Automatic Transmission Power Flow Diagram - 1 Position (Deceleration)

  Courtesy of AMERICAN HONDA MOTOR CO., INC.