Operation

OPERATION





Signals from the input speed sensors (6, 8) are recorded in the transmission control module (TCM) together with the wheel and engine speeds and other information and are processed into an input signal for electronic control.


Input speed sensor N2 (6) records the speed of the front sun gear via the externally toothed disc carrier of the multiple-disc clutch K1 (10) and input speed sensor N3 (8) records the speed of the front planet carrier via the internally toothed disc carrier of multiple-disc clutch K1 (3).


RELATIVE SPEED SENSOR READINGS - NAG 1 TRANSMISSION





1. N2 measures (6) the speed of the Front Planetary Rear Annulus Assembly.
2. N3 measures (8) the speed of the K1 clutch
3. K1 clutch (N3 speed sensor) will show no rotation whenever the B1 Brake is applied. N3 = Zero in 1st, 5th and Reverse.
4. With the vehicle moving forward or reverse, N2 speed sensor reading will be greater than zero in all gears
5. Whenever the K1 clutch is applied (2nd, 3rd, and 4th) N2 will be equal to N3.
6. There is no speed sensor internal to the transmission that directly measures input shaft speed. However, when K1 is applied N2 equals input shaft/turbine speed.
7. The engine speed is fed to the TCM via can bus thus providing impeller speed.
8. There is no speed sensor internal to the transmission that directly measures output shaft speed. ABS wheel sensors provide output shaft speed.

Relative Speed Sensor Readings:

Based on the preceding chart, it appears that N3 sensor is redundant and provides no additional Information. However, the TCM needs to know Input Shaft/Turbine speed. Since the N2 sensor is not directly tied to the Input Shaft, the N3 sensor is required to inform the TCM to divide the N2 value by 0.6081 or 1.0000 to calculate actual Turbine speed.