GM Service Manual Online
For 1990-2009 cars only
2WD High Indicator Light: This parameter displays On when the transfer case shift control module commands the 2WD high indicator light On. The scan tool displays On or Off.

4WD High Indicator Light: This parameter displays On when the transfer case shift control module commands the 4WD high indicator light On. The scan tool displays On or Off.

4WD Low Indicator Light: This parameter displays On when the transfer case shift control module commands the 4WD low indicator light On. The scan tool displays On or Off.

Accessory Status: This parameter displays Not Active, and Active.

ATC Motor Init. Test: This parameter displays Not Initialized, Passed, Failed, or in Progress when the key off initialization sequence has occurred.

Auto 4WD Indicator Light: This parameter displays On when the transfer case shift control module commands the auto 4WD indicator light On. The scan tool displays On or Off.

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 Calibration Status : This parameter displays not learned, initial learn, and normal learn.

Clutch Coupling : This parameter displays the amount of clutch activation shown in percentage.

Front Axle Actuator: This parameter displays the voltage input to the front axle actuator from 0 - 25 volts.

Front Axle Actuator Status: This parameter displays either disengaged or engaged, engaged when the system is in Auto 4WD, 4WD, or 4WD Low modes, and disengaged when the mode is in neutral, or 2WD mode.

Front Axle Switch : This parameter displays either locked or unlocked depending on the feedback from the front axle actuator switch, which will be battery voltage when the vehicle is in a 4WD or Auto 4WD mode.

Incremental Impulse Sensor : This parameter displays the direction the incremental sensor is moving as clockwise or counter clockwise.

Incremental Position Sensor Direction : This parameter displays the pulse width modulated voltage signal being supplied to the incremental sensor via the transfer case control module.

Incremental Position Sensor : This parameter displays the position of the incremental sensor in degrees.

Incremental Position Sensor: This parameter displays the position of the incremental sensor in incremental sensor return voltage.

Mode Switch Return Voltage: This parameter displays the transfer case shift control switch return voltage from 0-7.5 volts.

Mode Switch Selected : This parameter displays the transfer case shift control switch mode currently selected by the driver.

Mode Switch Selected : This parameter displays the voltage being supplied to the transfer case shift control switch by the transfer case control module from 0-7.5 volts.

Motor Brake: This parameter displays the voltage being supplied to the transfer case motor brake via the transfer case control module from 0 to battery voltage.

Neutral Indicator Light: This parameter displays On when the transfer case shift control module commands the neutral indicator light On. The scan tool displays On or Off.

Rotational Position Sensor: This parameter displays the position of the rotational position sensor in degrees.

Rotational Position Sensor: This parameter displays the position of the rotational position sensor by displaying the rotational position sensor return voltage as read by the transfer case control module.

Run/Crank: This parameter displays the status of the run/crank signal to the transfer case control module as active or inactive.

Transfer Case Lock : This parameter displays the status of the transfer case lock as engaged or disengaged, the lock will be engaged in auto 4WD, 4WD, or 4WD low and disengaged in 2WD and neutral.

Transfer Case Motor : This parameter displays the current draw in amperage that the motor is currently drawing from the transfer case control module.

Transfer Case Position: This parameter displays the current mode the transfer case is in as indicated by the transfer case control module.

Trans. Fluid Temp.: This parameter displays the transmission fluid temperature in degrees Celsius.

TR Switch Status: This parameter displays the current gear the transmission is in.

Vehicle Speed: This parameter displays vehicle speed in kilometers per hour.

Software Part Number : This parameter displays the numbers or characters assigned to the current version of software used in the transfer case shift control module. The scan tool displays an alphanumeric value.

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.