Riviera V6-231 3.8L VIN L SFI (1991)
TCC Circuit
CIRCUIT DESCRIPTION:
The 4T60-E transaxle uses two solenoids to control shifting. Shift solenoid A and shift solenoid B. Refer to table below for solenoid operating sequence.
The PCM monitors the TPS and vehicle speed vs. engine speed to determine the correct shift points. If the PRNDL position indicates manual low
position, the PCM will keep both solenoids A and B energized until 5,400.0 rpm at which point the PCM will force a shift by de-energizing solenoid A.
Manual 2nd and manual 3rd are controlled hydraulically within the transaxle.
DIAGNOSTIC AIDS:
If the PCM, control circuitry, and shift solenoids are functioning properly and the transaxle still does not shift correctly, the problem may be the
hydraulic or mechanical.
GEAR
SOLENOID A
SOLENOID B
1st
CLOSED
CLOSED
2ND
OPEN
CLOSED
3RD
OPEN
OPEN
4TH
CLOSED
OPEN
OPEN = DE-ENERGIZED