The ATC Scan Tool Data Definitions contain a brief description of all ATC related parameters available on the scan tool. The list is in the order it appears on the scan tool.

TP (Throttle Position) Angle: Displays a range of 0-100 %. The TP Angle is computed by the VCM from the TP sensor voltage. This measurement is used by the transfer case shift control module to help anticipate load requirements demanded by the driver. The TP Angle should read 0 percent at idle and 100 percent at Wide-Open Throttle (WOT).

Front Propshaft Speed: Displays a range of 0-8192 RPM. This parameter indicates the rotational speed of the front propshaft.

Rear Propshaft Speed: Displays a range of 0-8192 RPM. This parameter indicates the rotational speed of the rear propshaft.

ATC Slip Speed: Displays a range of 0-8192 RPM. This parameter indicates the RPM difference between the front and rear propshafts.

Slip Adapt PWM: Displays a range of 0-100 %. This parameter indicates the Duty Cycle applied to the ATC motor.

Last Adapt Highest PWM: Displays a range of 0-100 %. This parameter indicates the highest duty cycle applied to the ATC motor during the last slip event.

Ignition 3: Displays a range of 0-25.5 volts. This parameter indicates the voltage measured by the transfer case shift control module at its ignition feed.

AWD Enabled: The scan tool displays Yes or NC. This parameter indicates if the transfer case shift control module is currently attempting to prevent front to rear propshaft slip.

AWD Lamp Open: The scan tool should always display No. This parameter is not used by S/T vehicles. This parameter indicates that an open or short to ground is sensed in the SERVICE AWD/4WD lamp circuit.

AWD Lamp Shorted: The scan tool should always display No. This parameter is not used by S/T vehicles. This parameter indicates that a short to power is sensed in the SERVICE AWD/4WD lamp circuit.

Motor A or B Short to Volts: The scan tool displays Yes or No. When the ATC motor relay is commanded off, YES indicates that voltage is sensed on either the Motor A or B terminals.

Motor A or B Short to Gnd.: The scan tool displays Yes or No. When the ATC motor relay is commanded on but the ATC transistor is commanded off, YES indicates that current is flowing through part of the circuit to a short to ground and that no voltage is sensed at the Motor B terminal.

Motor Ground Circuit Open: The scan tool displays Yes or No. When the ATC motor relay is commanded on and the ATC transistor is commanded on, YES indicates no current flow and system voltage is sensed at both Motor A and B terminals.

Motor A or B Circuit Open: The scan tool displays Yes or No. When the ATC motor relay is commanded on but the ATC transistor is commanded off, YES indicates no current flow and no voltage is sensed at the Motor B terminal.

Motor A or B Circuit Fault: The scan tool displays Yes or No. YES indicates that one of the above motor circuit faults has been detected.

Rear Propshaft Signal Fault: The scan tool displays Yes or No. YES indicates a DTC C0300 (Rear Speed Sensor Malfunction) has been detected, but the code will not set unless the fault is present for 30 seconds.

Front Propshaft Signal Fault: The scan tool displays Yes or No. YES indicates a DTC C0305 (Front Speed Sensor Malfunction) has been detected, but the code will not set unless the fault is present for 30 seconds.

Software ID: The scan tool displays a four-digit number. This parameter indicates the transfer case shift control module calibration version number.

GM Part Number: The scan tool displays an eight-digit number. This parameter indicates the transfer case shift control module GM software number.