Circuit/System Verification

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

Vehicle OFF, allow the engine to cool to be within the temperatures listed in the Conditions for Running the DTC.
Engine running.
Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. 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
  Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Go to next step: If the DTC is not set
Verify that none of the conditions listed below exists with the air intake system:
- Damage, restriction, or modification
- Dirty or deteriorating air filter element
- Crankcase ventilation system for correct operation
- Water intrusion
- Vacuum leak and other unmetered air downstream of the mass air flow (MAF) sensor
- Intake manifold leak
- If any of the above conditions exist
  Repair as necessary.
- Go to next step: If none of the conditions exist
Verify that none of the conditions listed below exists with the exhaust system:
- Exhaust leak
- Damaged, restricted, or modified exhaust system - Refer to Symptoms - Engine Exhaust .
- If any of the above conditions exist
  Repair as necessary.
- Go to next step: If none of the conditions exist
If all of the above conditions test normal, inspect for an engine mechanical condition that could alter the air flow into the combustion chamber. Refer to Symptoms - Engine Mechanical .
- Go to next step: If the DTC does not set
All OK.