Steady State Adapts: Notes
The PCM/TCM monitors the ISS and the VSS after an upshift in order to determine the amount of clutch slippage. If excessive slippage is detected, then the PCM/TCM will adjust the current to the PC solenoid valve in order to increase the line pressure to maintain the proper gear ratio for the commanded gear.
The TAP information is divided into 13 units, called cells. The cells are numbered 4 through 16. Each cell represents a given torque range. TAP cell 4 is the lowest adaptable torque range and TAP cell 16 is the highest adaptable torque range. It is normal for TAP cell values to display zero or negative numbers. This indicates that the PCM/TCM has adjusted line pressure at or below the calibrated base pressure.