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:
Front Bumper Fascia Center Support Bracket Replacement
Front Bumper Fascia Center Support Bracket Replacement
Callout
Component Name
Preliminary Procedure
Remove the front bumper fascia. Refer to Front Bumper Fascia Replacement.
1
Front Bumper Fascia ...
Tire and Wheel Runout Specifications
Tire and Wheel Runout Specifications
Application
Specification
Metric
English
Tire and Wheel Assembly– Lateral and Radial
Off-Vehicle
1.27 mm
0 ...
Park - Engine Running (Gen 1)
When the gear selector lever is in the Park (P) position, fluid is drawn into
the pump through the transmission fluid filter assembly. Line pressure is then directed
to the following valves:
Fluid Pressure Directed in Preparation for a Shift
Manual Valve
Mechanically controlled by ...
0.0073