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:
Safety Belt Reminders
Driver Safety Belt Reminder Light
There is a driver safety belt reminder light on the instrument cluster.
When the vehicle is started, this light flashes and a chime may come on to remind
the driver to fasten their safety belt. Then the light stays on solid until the
belt is buckled. This cy ...
Driving on Snow or Ice
Drive carefully when there is snow or ice between the tires and the road, creating
less traction or grip.
Wet ice can occur at about 0°C (32°F) when freezing rain begins to fall, resulting
in even less traction. Avoid driving on wet ice or in freezing rain until roads
can be treated with sa ...
Front Seat Belt Guide Adjuster Replacement (with AHU)
Front Seat Belt Guide Adjuster Replacement
Callout
Component Name
Preliminary Procedures
Remove the center pillar upper trim panel. Refer to Center Pillar Upper
Trim Panel Replacement.
1
Driver ...
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