Circuit/System Verification

WARNING: This page is about a different car, the 2023 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.

Ignition - On/Vehicle - In Service Mode
Verify there are no DTCs set related to the following component/system:
- K20 Engine Control Module
- Serial Data
- If a related DTC is set
  Refer to: Diagnostic Trouble Code (DTC) List - Vehicle
- Go to next step: If a related DTC is not set
Clear the DTCs.
Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Verify the DTC does not set.
- If the DTC sets
1. Ignition/Vehicle - Off
2. Replace the component: K20 Engine Control Module
3. Operate the vehicle within the Conditions for Running the DTC.
  Verify the DTC does not set.
  - If the DTC sets - Replace the component: K71 Transmission Control Module
  - Go to next step: If the DTC is not set
4. All OK.
- Go to next step: If the DTC is not set
All OK.