GM Service Manual Online
For 1990-2009 cars only

Important: 

   • New CVRSS control modules must be calibrated after installation. DTC C1658 is stored in the memory of new Continuously Variable Road Sensing Suspension control modules and will not clear until the module is calibrated.
   • The scan tool must have the latest version chassis application program.

  1. Connect the scan tool to the Data Line Connector (DLC).
  2. Turn the ignition ON with the engine off.
  3. Proceed per the instructions on the scan tool readout.
  4. Perform the ALC Trim Height Adjustment. Refer to Trim Height Adjustment