Description & Operation: Notes

Input signals from sensors are sent to the Powertrain Control Module (PCM). The PCM can determine when the time and conditions are right for a shift, coast braking or converter clutch application. The PCM can also determine line pressure needed to optimize shift feel.

Five electronic solenoids accomplish these functions as follows:

3 On/Off solenoids for shifting.
One Pulse-Width Modulator (PWM) solenoid for torque converter clutch control.
One Electronic Pressure Control (EPC) solenoid for line pressure control.

PCM has built-in self-diagnosis, fail-safe code and Diagnostic Trouble Code (DTC) display for the main input sensors and solenoid valves.

NOTE: In addition to transmission fault codes, engine-related fault codes may be output during QUICK TEST procedure. These fault codes pertain to engine performance and must be repaired first as engine performance will greatly affect transmission operation. For information and testing procedures of engine-related fault codes and components, see appropriate TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE section.