Sunroof/Sunshade Motor Initialization

An inoperative sunroof and/or sunshade (RPO C3U) may be found on some 2018-2020 Equinox and Terrain models. The inoperative condition may be the result of the sunroof programming losing initialization.

Before replacing any parts or making any repairs to the sunroof, perform the Sunroof Motor/Actuator Initialization/Tech Process using the sunroof/sunshade open and close switches. (Fig. 21) Refer to Sunroof/Sunshade Motor Initialization in the appropriate Service Information.


Fig. 21


Initialization Procedure

Initialization refers to the sunroof system learning the reference location of the hard stop. Initialization should be performed the first time the system is powered, if the sunroof/sunshade has lost calibration or has a false reversal, if the motor assembly has been removed or replaced, or if the glass is adjusted after sunroof/sunshade initialization has already been completed.

Until the motor assembly has been initialized, the express-open and express-close switch inputs and manual open inputs are disregarded.

When performing the initialization procedure:

  • The sunroof motor should be calibrated before the sunshade motor.
  • If the initialization fails, disconnect the battery to reset the sunroof and sunshade motors. Wait one minute before reconnecting the battery.
  • If a sunroof or sunshade switch is held for more than 10 seconds after the glass or sunshade has completed its learn cycle, the sunroof can set a “stuck switch” fault code. Perform the battery disconnection procedure.
  • The control module provides obstacle blockage detection. If the initialization is not carried out completely, the sunshade may stop and reverse slightly when it gets to the location where it needs to push down the windscreen.


If sunroof operation does not function normally after initialization, continue with the recommended diagnostics in the Service Information.


– Thanks to Rob Smith

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