Adapt Function

The 4T65-E transmission uses a line pressure control system, which has the ability to continuously adapt the system's line pressure. This compensates for normal wear of the following parts:
^ The clutch fiber plates
^ The seals
^ The springs

This learning feature is similar to that which is used for fuel control and idle position.

The Powertrain Control Moduel (PCM) maintains the following adapt parameter for the transmission:
Upshift Adapt - The PCM monitors the Automatic Transmission Input (Shaft) Speed Sensor (A/T ISS) and the Vehicle Speed Sensor (VSS) during commanded shifts in order to determine if a shift is occurring too fast or too slow. The PCM adjusts the signal to the transmission Pressure Control Solenoid (PCS) valve in order to maintain a set shift feel.

Transmission adapts must be reset whenever the transmission is overhauled or replaced. In order to reset transmission adapts, select the following:
1. Scan tool
2. Miscellaneous test
3. A/T outputs
4. Clear or reset all adapts