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:
Tire and Wheel Removal and Installation
Special Tools
CH-41013 Rotor Resurfacing Kit
CH-42450-A Wheel Hub Resurfacing Kit
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
Remove the wheel cover ...
Vehicle, Engine and Transmission ID and VIN Location, Derivative and Usage
The vehicle identification number (VIN) plate is the legal identifier of the
vehicle. The VIN plate is located on the upper left corner of the instrument panel
(I/P) and can be seen through the windshield from the outside of the vehicle:
Vehicle, Engine and Transmission ID and VIN Loca ...
Clutch System Description and Operation
Clutch Spin Down Time
Inspect the clutch spin down time as follows:
Apply the parking brake and block the vehicle wheels.
Shift the manual transmission into NEUTRAL.
Start the engine. Run the engine at idle speed.
Engage the clutch.
Disengage the clutch. Wait 9 seconds.
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