Your vehicle is fitted with the 6T75 6 speed automatic transmission.
To access the input speed sensor, you will need to drain the transmission fluid and remove the oil pan. Once the oil pan is removed, next you will need to remove the valve body. See image 4, item 18.
It is recommended to fit a new oil pan gasket(7N266), see image 3.
Once removed you will see the input and output speed sensors, see image 1 below.
I have also attached a wiring diagram to check the wiring from the speed sensor back to the TCM.
How to check wiring:
How to check fluid level for the 6T75 transmission:
Images (Click to make bigger)
Monday, August 7th, 2023 AT 9:34 AM