Join Date: Mar 2009
Location: Central Illinois
Here is a rundown of signals the PCM uses as inputs to control the transmission:
You will need a VSS (Vehicle Speed Sensor) input.
A TPS for the throttle position feedback
The PCM also uses the PIP signal to be used as an input in determining shift scheduling and (EPC/line pressure).
The PCM also uses the Air Conditioning Clutch (ACC) signal as an input to determine EPC when the ACC is engaged to compensate for the additional load on the engine.
The Manifold Absolute Pressure (MAP) Sensor is used as an input to determine shift schedule and EPC for altitude operation.
The Low Range Switch (4x4 models) is used to Modify the shift schedule for 4x4L transfer case gear ratio.
Transmission Operating Temperature (TOT) Sensor: The Transmission Operating Temperature (TOT) sensor is located on the solenoid body in the transmission sump. It is a temperature-sensitive device called a thermistor. It sends a voltage signal to the PCM. The voltage signal varies with the transmission oil temperature. The PCM uses this signal to determine whether a cold start shift schedule is necessary. The cold start shift schedule lowers shift speeds to allow for the reduced performance of cold engine operation.
Manual Lever Position Sensor (MLPS): Sends a signal to the PCM. This indicates the position of the shift lever (P, R, N, (D), 2 or 1).
With that being said you can use an aftermarket transmission controller, but they are pricey.