Circuit/System Verification

WARNING: This page is about a different car, the 2023 GMC Sierra 3500 HD and 2023 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Verify the condition does not exist: Incorrect fluid level or condition - Refer to: Transmission Fluid Level and Condition Check
- If a condition exists
  Repair or replace as necessary
- Go to next step: If no condition exists
Ignition - On/Vehicle - In Service Mode
Clear DTCs
Road test the vehicle. - Refer to: Road Test
Verify DTC P0716, P0717, P0721, P0722, P0723, P077C, P077D, P07BF, P07C0, P172A, P172B, P176B, P176C, P176D, P1783, P178F, P17C5, P17C6, P17CC, P17CD, P17CE, P17D3, P17D6 is not set.
- If any of the DTCs are set
  Refer to: Diagnostic Trouble Code (DTC) List - Vehicle
- Go to next step: If none of the DTCs are set
Verify that no DTC listed in the DTC Descriptor Category is set.
- If any DTC listed in the DTC Descriptor Category is set
  Refer to: Diagnostic Fault Information
- Go to next step: If none of the DTCs listed in the DTC Descriptor Category is set
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.Refer to: Road Test
Verify that no DTC listed in the DTC Descriptor Category is set.
- If any DTC listed in the DTC Descriptor Category is set
  Refer to: Diagnostic Fault Information & Verify the conditions listed in the table do not exist
- Go to next step: If none of the DTCs listed in the DTC Descriptor Category is set
All OK.