MLPS: Manual Lever Position Sensor
(from the Service Manual):
The manual lever position sensor (MLP sensor):
The powertrain control module (PCM) (12A650) monitors the voltage across a series of step-down resistors that corresponds to the position of the manual control lever (7A256). The powertrain control module uses this information in determining desired gear and EPC pressure.
Permits the engine to start only in the PARK and NEUTRAL positions.
Activates the back-up lamps in the REVERSE position
TCC: Torque Converter Clutch (it's part of the torque converter, based on a drawing in the service manual- see part #5 in the following drawing)
TCC Solenoid: Torque Converter Clutch Solenoid (it's inside the Main Control Valve Body)
More info from the service manual:
The powertrain control module (PCM) (12A650) and its input/output network control the following transmission operations:
Line pressure (shift feel).
Torque converter clutch.
The transmission control is separate from the engine control strategy in the PCM, although some of the input signals are shared.
The powertrain control module receives some input signals from engine-related sensors:
Mass airflow sensor (MAF sensor) (12B579) .
Engine coolant temperature sensor (ECT sensor) (12A648)
Barometric pressure sensor, etc.
These signals provide information to the powertrain control module about the load and climate under which the engine is operating. Some other inputs are based on driver inputs, such as accelerator pedal position which is related to the powertrain control module by the throttle position sensor (TP sensor) (9B989). Still other inputs are provided by:
Output shaft speed sensor.
Manual lever position sensor (controlled by driver placement of the shift lever).
Transmission oil temperature sensor (TOT sensor) (7H141)
Using all of these input signals, the powertrain control module can determine when the time and conditions are right for a shift or torque converter clutch application. The powertrain control module can also determine the line pressure needed to optimize shift feel. To accomplish these functions, the powertrain control module controls four electronic solenoids:
Two On/Off shift solenoids (7G484).
One pulse- width modulated torque converter clutch solenoid (TCC solenoid) (7G136) for torque converter clutch (TCC) control or "controlled slip" of the torque converter clutch.
An electronic pressure control (EPC) solenoid for line pressure control