Powertrain Control Module (Pcm)
The PCM receives information from various input devices and uses this information to control the following output devices: shift solenoids, band apply solenoid, Torque Converter Clutch (TCC) solenoid and pressure control solenoid (force motor).
The PCM contains a self-diagnostic system which stores a Diagnostic Trouble Code (DTC) if a failure or problem is present in the transmission electronic control system. If a specific failure or problem is present, CHECK TRANS light will flash to inform driver of a problem. See DTC IDENTIFICATION table. CHECK TRANS light is located on left side of instrument panel, below air vent.
DTCs may be retrieved to determine transmission problem area. For information on retrieving DTCs, see SELF-DIAGNOSTIC SYSTEM . The PCM contains a fail-safe system. When a specific failure or problem is present in the transmission electronic control system, the PCM may go into back-up mode using pre-programmed values, allowing vehicle to be driven. The CHECK TRANS light may flash to inform driver of a problem. See DTC IDENTIFICATION table.
Vehicle can be driven in back-up mode, but shifting must be done manually. When manually shifting transmission, if gearshift lever is placed in "D" or "3" position, transmission remains in 4th gear. If gearshift lever is placed in "2" position, transmission remains in 3rd gear. If gearshift lever is placed in "L" position, transmission remains in 1st gear. If gearshift lever is placed in "R" position, transmission will shift into reverse. Back-up mode may be cleared by turning ignition off, then back on again.
For additional information on the self-diagnostic system, see SELF-DIAGNOSTIC SYSTEM . The PCM is located below center of instrument panel. See Fig 1 .