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K4 Assist Step Control Module: Scan Tool Information

WARNING: This page is about a different car, the 2021 GMC Sierra 3500 HD and 2021 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Scan Tool Data Parameters

Parameter	Expected Value	Description
Operating Conditions: Ignition ON
Battery Voltage	Varies	Current voltage of battery.
Assist Step System Status	Normal	Scan tool displays Unknown, Enabled, Disabled, or Extended.
Driver Door Ajar Switch	Door Closed	Scan tool displays Door Closed or Door Open.
Passenger Door Ajar Switch	Door Closed	Scan tool displays Door Closed or Door Open.
Left Rear Door Ajar Switch	Door Closed	Scan tool displays Door Closed or Door Open.
Right Rear Door Ajar Switch	Door Closed	Scan tool displays Door Closed or Door Open.
Left Assist Step Learn Status	Yes	Scan tool displays Learned if the left step learn has been completed.
Left Assist Step Position	Count Value	Scan tool displays the current left step position count.
Right Assist Step Learn Status	Yes	Scan tool displays Learned if the right step learn has been completed.
Right Assist Step Position	Count Value	Scan tool displays the current right step position count.
Right Assist Step Command	Retract Completed	Scan tool displays Unknown, Extend Completed, Retract Completed, Extending, Retracting, Error, Object Detected, or Timeout.
Left Assist Step Command	Retract Completed	Scan tool displays Unknown, Extend Completed, Retract Completed, Extending, Retracting, Error, Object Detected, or Timeout.
Assist Step Disable Switch	Inactive	Displays Active if switch is pressed.
Left Assist Step Kick Switch	Inactive	Displays Active if switch is pressed.
Right Assist Step Kick Switch	Inactive	Displays Active if switch is pressed.

Scan Tool Output Controls

Output Control	Description
Left Assist Step Motor	Allows scan tool control of left assist step.
Right Assist Step Motor	Allows scan tool control of right assist step.