Semi Automatic Mode

This mode is used for 4×4 or racing where the driver controls the gears of the transmission manually but the TCU will still do safety protection against over revving. You can set it up so that the transmission to assist the driver in routine tasks like gearing back automatic so you pull off in the right gear. Or shift up when the engine limiter is reached. This is handy for drag racing. This mode is also handy to pull off in higher gears or keep it in that gear for Dyno’s etc.

This mode is used with Tiptronic in Semi-Automatic selection. The buttons will shift gears up or down if it is in the set limits. Below are a few rules on how to set it up. If the TCU seems non responsive it is one of these settings that will keep it from responding.

Procedure of Tuning.
The next steps should have been done in your profile 1 automatic mode.

  1. First go through the setup and enter all the relevant settings that you do know.
  2. Calibrate the TPS sensor.
  3. Start the engine and check the rev counter calibration is correct, then save the data and switch the engine off.
  4. Switch the ignition on and do the following settings while you are standing still.
  5. Start with the following option settings.


Set the profiles in a typical setup like below.

Notice how the graphs are drawn. All the dots are on the top or bottom. This means the marker cannot move above or below the horizontal lines and activate up or down shift. It can only move left or right of the vertical lines. You may have any variation you need but this one is popular for most control by the driver. Set each gear profile according to the following rules. Each scenario will be discussed.

Gear Shift Time
This time must be long enough to allow the manual transmission to complete the shift and the next gear to take up the drive train without slip.

Slow Gear Down
This block will force a gear down if the speed falls below this value and the marker is left of the blue bottom left dot. In this example the blue revs are 1700 and the marker is 1900 so it will not gear down even if the speed is lower than 23 Kph. This will prevent gear down if the drive-wheels spin in mud for example. (Speed in this case must be taken from the non-drive wheels).

Preventing Automatic Down Shift
If you do not want the transmission to downshift automatically, move the vertical red line to below the Idle RPM’s. In the example this line is on 600 RPM and the engine idles at 800 RPM. Also make the gear down speed 0 so that it will not activate down shift. Only way to down shift from here is with the buttons.

Preventing Automatic Up Shift
If you do not want the transmission to upshift when engine limiter is reached, then move the blue vertical line higher than the engine limiter. In the example this line at 7400 and the engine limiter is 7000 RPM max. So it will not go beyond the blue line and force an up shift.

Preventing Tiptronic Down Shifts
There are 2 limits that will prevent gear down with the tiptronic buttons. Vehicle Speed must be less than Kick down speed and the engine RPM must be less than the top right red dot. If revs are higher than 2500 in the example or speed are more than 55 Kph, then the downshift button is ignored.

Preventing Tiptronic Up Shifts
There are 2 limits that will prevent gear up with the tiptronic buttons. Vehicle Speed must be more than the next gear’s Gear Down Speed otherwise that gear will force it back. The engine revs must be higher than the Blue bottom left dot. In this example it is 1700 rpm. If it is less, then the up shift button is ignored.

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