GM Service Manual Online
For 1990-2009 cars only
ATC Application: This parameter displays the model number assigned to the transfer case. The scan tool displays a numeric value.

ATC Slip Speed: This parameter displays the RPM difference between the front and rear propshafts. The scan tool displays a range of 0-8,192 RPM.

Battery Voltage: This parameter displays the voltage measured by the transfer case shift control module at the transfer case shift control module battery feed. The scan tool displays a range of 0-25.5 volts.

Clutch Pedal Engaged: This parameter displays On when the clutch pedal is depressed. The scan tool displays On or Off.

Current Slip Adapts: This parameter displays corrective adjustments made by the transfer case shift control module for wheel slip events. The scan tool displays a numeric value.

Encoder Gear Position: This parameter displays the mode the transfer case is currently in.

Encoder Return Voltage: This parameter displays the voltage measured by the transfer case shift control module at the encoder signal return. The scan tool displays a range of 0-7.5 volts.

Encoder Supply Voltage : This parameter indicates the voltage measured by the transfer case shift control module at the encoder power supply. The scan tool displays a range of 0-7.5 volts.

Front Propshaft Speed: This parameter displays the rotational speed of the front propshaft. The scan tool displays a range of 0-8,192 RPM.

Ing. Cycles Since Last Current DTC: This parameter displays how many ignition cycles have occurred since last current DTC was set. The scan tool displays a numeric value.

Rear Propshaft Speed: This parameter displays the rotational speed of the rear propshaft. The scan tool displays a range of 0-8,192 RPM.

Service 4WD Lamp: This parameter displays On if the transfer case shift control module commands the Service 4WD lamp, or message, On. The scan tool displays On or Off.

Slip Adapt PWM: This parameter displays the duty cycle applied to the transfer case encoder motor. The scan tool displays a range of 0-100 percent.

Total Slippage: This parameter displays the total slippage of both the front and rear propshafts. The scan tool displays a range of 0-8,192 RPM.