2021 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE

Maintenance Mode

Display Contents of display Index No.
Brake Maintenance Mode Used when inspecting and repairing parts related to rear brake. Refer to PARKING BRAKE>PARKING BRAKE SYSTEM>OPERATION>BRAKE MAINTENANCE MODE .
Reading of parameter: ECM to SSM Read VDC Control Module parameter data. Refer to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC Control Module & H/U)>MAINTENANCE MODE>VDC Control Module PARAMETER READING .
Writing of parameter: SSM to ECM Write the parameter data to the VDC Control Module. Refer to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC Control Module & H/U)>MAINTENANCE MODE>VDC Control Module PARAMETER WRITING .
Select Parameter Select and register parameters in the VDC Control Module. Refer to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC Control Module & H/U)>MAINTENANCE MODE>VDC Control Module PARAMETER SELECTION .
Confirm on parameter Parameters registered in the VDC Control Module are displayed. Refer to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC Control Module & H/U)>MAINTENANCE MODE>VDC Control Module PARAMETER CHECK .
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.