Special gearchange programs

Special gearchange programs are selected automatically depending on the engine load. This function is available to normal and sport programs.

The shifts occur at higher engine RPM and the gear is engaged for longer if the control module senses that the load does not decrease. These shifting programs are in place to avoid unnecessary up and downshifting, for example, when driving on long uphill stretches with a trailer as well as to prevent overheating of the transmission fluid.

The special gearchange programs are not activated at speeds above 150 km/h. If a special gearchange program is active when the vehicle accelerates beyond 150 km/h, the program is retained until the control module senses that a more suitable gearchange pattern can be selected.

Fig 1: Gear Change Program Communication Flow Diagram (1 Of 2)

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Fig 2: Gear Change Program Communication Flow Diagram (2 Of 2)

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Special gearchange programs will be disengaged if:

• The winter program is selected.
• The ignition key is turned to OFF.
• The load decreases and a special gearchange pattern is no longer required.
• CHECK GEARBOX lamp lights up.
  Fig 3: Gear Change Program Disengagement Condition Diagram

  Courtesy of SAAB-SCANIA OF AMERICA, INC.