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Overview Transmission Control

Fig 1: Transmission Control Components
GF0043282Courtesy of FORD MOTOR CO.
Item Part Number Description
1 - PCM
2 - Data Link Connector (DLC)
3 - Throttle Position (TP) sensor
4 - Mass Air Flow (MAF) and Intake Air Temperature (IAT) sensors
5 - Crankshaft Position (CKP) sensor
6 - Output Shaft Speed (OSS) sensor
7 - Turbine Shaft Speed (TSS) sensor
8 - Transmission Range (TR) sensor
9 - Transmission Fluid Temperature (TFT) sensor
10 - Overdrive (O/D) switch
11 - Stoplamp switch
12 - Brake Shift Interlock Actuator (BSIA)
13 - Ignition key lock solenoid
14 - A/C relay
15 - Accelerator Pedal Position (APP) sensor
16 - Solenoid valves in the valve body
17 - Powertrain warning indicator in Instrument Cluster (IC)
18 - O/D indicator in IC

The PCM and its input/output network controls the following operations:

The transaxle control is separate from the engine control strategy in the PCM, although some of the input signals are shared. When determining the best operating strategy for transaxle operation, the PCM uses input information from certain engine-related and driver-demand related sensors and switches.

In addition, the PCM receives input signals from certain transaxle-related sensors and switches. The PCM also uses these signals when determining transaxle operating strategy.

Using all of these input signals, the PCM can determine when the time and conditions are right for a shift, or when to apply or release the TCC. It will also determine the best line pressure needed to optimize shift feel. To accomplish this, the PCM uses output solenoids to control transaxle operation.