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General Information

GENERAL INFORMATION
The TCM receives input information and continuously processes this information through its logic circuits to perform all of the control functions that it is designed to perform. However, some of these control functions are internal to the TCM, while other control functions are performed when the TCM provides some type of output signal to another control device or module. The following is a description of TCM input sensors and output devices.

The TCM uses various inputs to determine when to upshift or downshift and when to engage or disengage the Torque Converter Clutch (TCC). The TCM also uses these inputs for continuous feedback data for controlling shift quality. Without any input, the TCM has no way to determine the state of the transaxle and cannot control its operation as designed.

Some of the inputs to the TCM are direct, or hard-wired inputs, while others are shared with other components through the CCD Bus.

DIRECT (HARD-WIRED) TCM INPUTS
- Battery Feed
- Ignition RUN Signal
- Cranking Signal
- Throttle Position Sensor (TPS) Signal
- Engine speed signal (Distributor or DIS Crankshaft Position Sensor)
- Input Speed Sensor Signal
- Output Speed Sensor Signal
- Transmission Range Sensor**(Includes Transmission Temperature Sensor)
- Transmission Control Relay (Switched Battery)
- L/R Pressure Switch Signal
- 2-4 Pressure Switch Signal
- O/D Pressure Switch Signal
- Park/Neutral Position Switch*
- PRNDL Switch*
- Torque Reduction Request Line (TRD Link)

INDIRECT (CCD BUS) TCM INPUTS
- Target Idle Speed
- Engine Coolant Temperature (ECT) Sensor
- Battery Temperature Sensor*
- Brake Switch
- Engine and Body Identification
- Engine Speed (Verifies Direct Input Engine Speed Signal)
- Speed Control ON/OFF Switch
- Speed Control Set Speed
- A/C Clutch Engagement
- Vehicle Identification Number (VIN)
- Manifold Absolute Pressure (MAP) Sensor
- Torque Reduction Confirmation Response
- Relative Throttle Position (Beginning in 1998)

*: UP TO 1995
**: BEGINNING IN 1996