Group 43 MID 130 Transmission Control Unit Transmission Identification Each transmission has two identification tags. One is found on the top of the clutch housing and the other is found on the back of the range housing. The transmission version can be readily identified by the following nomenclature table. Sensors Clutch Position Sensor The Clutch Position Sensor is located on the side of the clutch cylinder assembly (inside bell housing). Main Shaft Speed Sensor(s) The speed sensors are located on the control housing and measure the speed of the main shaft and the speed of the countershaft. The main shaft speed sensor is a electronic sensor with a hall element.
Using a hall element makes it possible to measure the rotation speed and rotation direction of the shaft. The countershaft speed sensor is an inductive sensor. Knowing the speed of the countershaft makes it possible to calculate the precise speed of every gear in the transmission. The speed sensor(s) are located in the transmission on the lower portion of the control housing. Output Shaft Speed Sensor The Output Shaft Speed Sensor is located on the side of the rear transmission housing. Range Cylinder Position Sensor There are four position sensors in the transmission control housing. These sensors measure the position of the specific air cylinder within the control housing.
The sensors are inductive and the inductive characteristics change depending on the position of the metal pin that follows the movements of the air cylinders. The Range Cylinder Position Sensor is located in the transmission on the lower portion of the control housing. 4 Make Volvo Transmission Model AT2512C, ATO2512C, AT2612D, ATO2612D, AT2812C, ATO3112C and ATO3112D Description A – Automatic T – Transmission O – Overdrive 25 – Torque Capacity 2500 Nm (1850 lb-ft) 26 – Torque Capacity 2600 Nm (2312 lb-ft) 28 – Torque Capacity 2800 Nm (2050 lb-ft) 31 – Torque Capacity 3100 Nm (2300 lb-ft) 12 – Number of forward gears C or D – Design Level