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Scan Tool Data Definitions

2-Wheel Steer Mode Lamp: Scan tool displays ON/OFF. The state of the mode indicator as commanded by the rear wheel steering control module.

4-Wheel Steer Mode Lamp: Scan tool displays ON/OFF. The state of the mode indicator as commanded by the rear wheel steering control module.

4-Wheel Steer-Tow Mode Lamp: Scan tool displays ON/OFF. The state of the mode indicators commanded by the rear wheel steering control module.

8-Digit GM Part Number: The scan tool displays the GM part number of the rear wheel steering control module.

Actual Rear Steering Angle: The scan tool displays the actual angle of the rear wheels. With a range of 0° to 12°.

Battery Voltage: The scan tool displays 0-16.0 volt. The scan tool displays the battery system voltage as monitored by the rear wheel steering control module.

Command 2-Wheel Steer: The scan tool displays ON/OFF. The scan tool displays ON when commanded by the scan tool while causing the 2-Wheel Steer LED to be illuminated. The scan tool displays OFF when commanded by the scan tool while causing the 2-Wheel Steer LED to be turned OFF.

Command 4-Wheel Steer: The scan tool displays ON/OFF. The scan tool displays ON when commanded by the scan tool while causing the 4-Wheel Steer LED to be illuminated. The scan tool displays OFF when commanded by the scan tool while causing the 4-Wheel Steer LED to be turned OFF.

Command 4-Wheel Steer-Tow: The scan tool displays ON/OFF. The scan tool displays ON when commanded by the scan tool while causing the 4-Wheel Steer and trailing LED to be illuminated. The scan tool displays OFF when commanded by the scan tool while causing the 4-Wheel Steer and trailering LED to be turned OFF.

Commanded Rear Steer Left: The scan tool displays ON/OFF. The scan tool causes the rear wheels to turn to the left during an ON command and return to normal operation during the OFF command.

Commanded Rear Steer Right: The scan tool displays ON/OFF. The scan tool causes the rear wheels to turn to the right during an ON command and return to normal operation during the OFF command.

Digital SWPS Phase A-Steering Wheel Position Sensor: The scan tool displays High/Low. Phase A signal of the Steering Wheel Position Sensor should change states as the steering wheel is rotated left or right. Each transition from high to low represents one degree.

Digital SWPS Phase B-Steering Wheel Position Sensor: The scan tool displays High/Low. Phase B signal of the Steering Wheel Position Sensor should change states as the steering wheel is rotated left or right. Each transition from high to low represents one degree.

Hall Sensor Reference: The scan tool displays 12 V. The hall sensor reference is the supply voltage of the hall sensor.

Ignition 3: The scan tool displays 0-16 volts. Ignition 3 is hot in run mode only.

Ignition Cycles Since Last Fault: The scan tool displays 0-100. The number of ignition cycles since the last fault occurred.

Motor Current: The scan tool displays 0-85-amp Max, A typical range of 20-50 Amps. Motor current is the range of the current in the rear steering motor during normal operation.

Motor Relay Commanded State: The scan tool displays ON/OFF. When system is in RUN then the relay will be ON, if system is shut down for any reason the relay will be OFF.

Motor Relay Feedback State: The scan tool displays ON/OFF. The actual state of relay.

Rear Steer Mode Actual: The scan tool displays: 2WS, 4WS, 4WS Tow. The actual state of the rear wheel steering system.

Rear Steer Mode Request: The scan tool displays: 2WS, 4WS, 4WS Tow. The requested state of the rear wheel steering system.

Rear Steer Select Switch: The scan tool displays ON/OFF. The rear wheel steering selection switch allows the driver to change steering modes. Display shows ON with the switch depressed.

Rear Wheel Centering 1: The scan tool displays 2.5 volts. The parameter, represented as a voltage, that monitors the rear wheel position 1 signal. When the rear wheel sensor is centered, the scan tool displays 2.5 volts.

Rear Wheel Centering 2: The scan tool displays 2.5 volts. The parameter, represented as a voltage, that monitors the rear wheel position 2 signal. When the rear wheel sensor is centered, the scan tool displays 2.5 volts.

Rear Wheel Position 1: The scan tool displays 0.25-4.75 volts. This parameter monitors the first of two rear wheel sensor signals for out of specified operation range.

Rear Wheel Position 2: The scan tool displays 0.25-4.75 volts. This parameter monitors the second of two rear wheel sensor signals for out of specified operation range.

Requested Rear Steering Angle: The scan tool displays 0-12 degrees. This is the command coming from the rear wheel steering module.

Sensor Supply Voltage: The scan tool displays approx 5.00 volts. The sensor supply voltage is the supply voltage of the rear wheel position sensor.

Steering Wheel Angle: The scan tool displays -609 to +609 degrees. The steering wheel angle parameter indicates the direction of rotation of the steering wheel.

Steering Wheel Angle (TBC): This parameter is displayed in degrees from -225 to +225. This angle represents the analog signal communicated to the rear wheel steering control module from the BCM via class 2 communication.

Steering Wheel Sensor Signal: This parameter is displayed in BCM Data. The scan tool displays from 0.25 to 4.75 volts. The signal is a linear signal that measures its minimum voltage when the steering wheel is turned approximately 1 full turn to the right from center. The scan tool displays approximately 2.5 volts with the steering wheel centered.

SWPS Marker Pulse: The scan tool displays HIGH/LOW. The marker pulse is used to center the rear wheels during the learn alignment procedure.

Vehicle Speed: The scan tool displays 0 to 159 mph. The rear wheel steering control module receives vehicle speed information, 0-255 km/h (0-159 mph) from the PCM vehicle speed signal circuit. The PCM calculates the vehicle speed from VSS signal.