Shift Solenoid: Description and Operation

Torque Converter Clutch (TCC) Circuit:

Purpose:
The 4T60-E is an electronically shifted transaxle. With in the transaxle are 4 solenoids for shift and TCC control. The shift A solenoid is energized for first and forth gear operation. Sift B solenoid is energized for first and second gear operation. The other two solenoids are for TCC operation.

Operation:
When the ignition switch is turned "ON", both shift solenoids receive 12 volts from CKT 241. The PCM will ground CKT 1223 and CKT 1222 for first gear until a shift to second gear is commanded. When vehicle speed and TP sensor reach calibrated values the PCM will turn "OFF" the ground for the shift A solenoid and second gear is engaged. Further increases in speed will result in the PCM turning "OFF" the ground for the shift B solenoid, engaging third gear. In third gear, both solenoid are de-energized. In forth gear, only the shift A solenoid is energized.

All PRNDL indications are ignored as far as transaxle shifting is concerned except for manual low gear. If the PRNDL inputs indicate manual low has been selected the PCM will keep both shift solenoids energized until 5400 rpm, when the PCM will force a shift by de-energizing the shift A solenoid. Manual second and third are controlled hydraulically within the transaxle.

Location:
The shift control solenoids are located inside the transaxle.