Nissan Maxima Service and Repair Manual: Shift control system

System Diagram

NOTE: The gear ratio is set for each position separately.

System Description

In order to select the gear ratio that can obtain the driving force in accordance with driver's intention and the vehicle condition, TCM monitors the driving conditions, such as the vehicle speed and the throttle position, selects the optimum gear ratio, and determines the gear change steps to the gear ratio. Then TCM sends the command to the step motor, controls the inflow/outflow of line pressure from the primary pulley to determine the position of the moving-pulley and controls the gear ratio.

"D" POSITION

Shifting over all the ranges of gear ratios from the lowest to the highest.

"M" POSITION

By moving the selector lever to + side or - side, the manual mode switch is changed over, and shift change like M/T becomes possible following the changing gear set line step by step.

"DS" POSITION

•  When the selector lever is put in the manual shift gate side, the driver can drive more sporty than "D" position.
•  "DS" mode can be switched according to the following method.
•  When the selector lever is in the "D" position, shifting the selector lever to manual shift gate enables switching to "DS" mode.
•  When in "DS" mode, shifting the selector lever to the main gate enables to cancel "DS" mode.
•  After switching to manual mode with paddle shifter, switching to "DS" mode can not be enabled even when the selector lever is shifted to the manual gate. (With paddle shifter)

DOWNHILL ENGINE BRAKE CONTROL (AUTO ENGINE BRAKE CONTROL)

When a downhill slope is detected with the accelerator pedal released, the engine brake will be strengthened up by downshifting so as not to accelerate the vehicle more than necessary.

ACCELERATION CONTROL

According to vehicle speed and a change of accelerator pedal angle, driver's request for acceleration and driving scene are judged. This function assists improvement in the acceleration feeling by making the engine speed proportionate to the vehicle speed. And a shift map that can gain a larger driving force is available for compatibility of mileage with driveability.

Component Parts Location

1.  CVT shift selector assembly (Manual mode select switch and manual mode position select switch)
2.  Secondary speed sensor
3.  CVT unit harness connector
4.  TCM
5.  Accelerator pedal position (APP) sensor
6.  Stop lamp switch
7.  Shift positioner indicator Manual mode indicator DS mode indicator
8.  Paddle shifters

Component Description

TRANSAXLE ASSEMBLY

EXCEPT TRANSAXLE ASSEMBLY