Aisin A750E Special Instructions Ver 3.3B

This Transmission operates with a lever that has mechanical positions for 12DNRP. What Toyota did was making 2 slide slots in the shifter that make switches to tell the TCU what you want. Position 1 has a slot for 1 – 2 and Position D has a slot for 4 – 5.

To understand this, look at the following positions of the shifter.

Position D – Here the TCU can select between 1st to 5th gear and only 4th and 5th gear has engine brake.
Position 2 – Here the TCU can select between 1st and 2nd and 3rd gear and only 3rd gear has engine brake
Position 1 – Here the TCU can select between 1st and 2nd gear. 2nd Gear will have engine brake and 1st not. If you want engine brake is 1st then you must select the Tiptronic Max Gear to 1st. So this means if your shifter is in position 1 and you select 2nd then 1st will not have engine brake. If you force 1st then you will have engine brake. The Tiptronic setting must be on one of the 3 modes.

There is a Timing Retard output that signals the ECU to retard timing during shift conditions. For performance applications shift harshness must be tuned in the ECU.

The transmission is momentarily put in second when the lever moves from N to D to soften Squad engagement.

In Drive mode lockup can be used in 3rd, 4th and 5th gears. In S4 it is used in 4th gear only.

The oil temperature sensor is a 3.5K sensor and the graph is calibrated for it. Put it on the 2K setting and the calibration value must be 100


Shifter positions on the display or real-time block will be 1,2,D,N,R,P.

The SL1 Orange graph is used for 5th gear shift pressure. The high line is high pressure. The low line is soft pressure. It should be tuned between approximately 40% to 70%. Start with 70% and lower if the shift is harsh.
The SL2 Green graph is used for 1st to 4th gear shift pressure. The high line is high pressure. The low line is soft pressure. It should be tuned between approximately 40% to 70%. Start with 70% and lower if the shift is harsh.
The SLT Blue line is line pressure. The high line is soft pressure. The low line is high pressure



Courtesy the Toyota manual.

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