Chevrolet Sonic Repair Manual: Transmission Adaptive Functions
The 6T30/40/45/50 transmission utilizes a line pressure control system during upshifts to compensate for the normal wear of transmission components. As the apply components within the transmission wear or change over time, shift time (the time required to apply a clutch) increase or decreases. In order to compensate for these changes, the transmission control module (TCM) adjusts the pressure commands to the various PC solenoids, to maintain the originally calibrated shift timing. The automatic adjusting process is referred to as ?daptive learning?and it is used to ensure consistent shift feel plus increase transmission durability. The TCM monitors the A/T input speed sensor (ISS) and the A/T output speed sensor (OSS) during commanded shifts to determine if a shift is occurring too fast (harsh) or too slow (soft) and adjusts the corresponding pressure control (PC) solenoid signal to maintain the set shift feel.
The purpose of the adapt function is to automatically compensate the shift quality for the various vehicle shift control systems. The adapt function is a continuous process that will help to maintain optimal shift quality throughout the life of the vehicle.
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF
in each shift lever position.
For automatic transmission vehicles, the ignition should turn to LOCK/OFF
onl ...
Transmission Assemble (Gen 1)
Special Tools
3-9506289 Universal Adapter
R-0007758 Holding Fixture
S-9407197 Differential Rotating Tool
S-9407198 Differential Bearing Race Wrench
For equivalent regional tools, refer ...
Other materials:
Cruise Control
: Press to turn the cruise control
system on and off.
RES/+: Move the thumbwheel up briefly to make the vehicle resume to a previously
set speed or hold upwards to accelerate. If cruise control is already active, use
to increase vehicle speed.
SET/−: Move the thumbwheel down briefly ...
DIC Operation and Displays
The DIC has different displays which can be accessed by using the DIC buttons
on the turn signal lever on the left side of the steering wheel. The DIC displays
trip, fuel, and warning messages if a system problem is detected. See Trip Computer and Vehicle Messages.
DIC Buttons
1. SET/C ...
Shift Control Housing Replacement
Removal Procedure
Set the parking brake.
Shift the transmission to the Neutral position.
Remove the battery tray. Refer to
Battery Tray Replacement.
Remove the brake master cylinder assembly from the
power brake booster. Refer to Master Cylinder Replacement.
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