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Home >> Cadillac >> 2021 >> XT5 Sport >> Repair and Diagnosis >> External Pages >> Different car >> Section 333 (Programming And Setup) >> Repair Instructions >> K84 Keyless Entry Control Module: Programming and Setup >> Replace and Program ECU or Reprogram ECU
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Replace and Program ECU or Reprogram ECU

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.

To program a replacement or an existing ECU, perform the following procedure:

  1. Install EL-49642  SPS programming support tool.
  2. Access the Service Programming System (SPS) and follow the on-screen instructions.
  3. On the SPS Supported Controllers screen, select K84 Keyless Entry Control Module - Programming and follow the on-screen instructions.
  4. At the end of programming, choose the "Clear All DTCs" function on the SPS screen.