Transmission Control Module
The TCM 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 force motor solenoid operation.
The TCM contains a self-diagnostic system, which stores Diagnostic Trouble Code (DTC) if failure or problem exists in transmission electronic control system. If a failure or problem exists in transmission electronic control system, the CHECK TRANS light will flash to inform driver of a problem. The CHECK TRANS light is located on instrument panel. See Figure or Figure .
The DTC may be retrieved to determine transmission problem area. For information on retrieving DTC, see SELF-DIAGNOSTIC SYSTEM . The TCM contains a fail-safe system. When failure or problem exists in transmission electronic control system, the TCM goes may go into back-up mode using pre-programmed values, allowing vehicle to be driven. The CHECK TRANS light on instrument panel may flash to inform driver of a problem.
Vehicle can be driven in back-up mode, but shifting must be done manually. When manually shifting transmission, if shift lever is placed in "D" or "3" position, transmission remains in 4th gear. If shift lever is placed in "2" position, transmission remain in 3rd gear. If shift lever is placed in "L" position, transmission remains in 1st gear. If shift lever is placed in "R" position, transmission will shift into reverse. Back-up mode may be cleared by turning ignition off and back on again.
For additional information on self-diagnostic system, see SELF-DIAGNOSTIC SYSTEM . The TCM is located below driver's side of instrument panel, near kick panel. See Fig 1 -Fig 4 .