Circuit/System Verification

WARNING: This page is about a different car, the 2022 Cadillac CT4. 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:
- B74 Manifold Absolute Pressure Sensor
- B75 Mass Airflow Sensor
- B111B Turbocharger/Supercharger Boost Pressure and Intake Air Temperature Sensor
- Q17 Fuel Injector
- Fuel Trim System
- 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
Verify the following conditions do not exist:
- Air Cleaner Element - Dirty/Water intrusion/Visible Damage
- Exhaust System
  - Leaking - Refer to: Exhaust Leakage
  - Loose Clamps
  - Missing components
  - Restrictions - Refer to: Restricted Exhaust
  - Visible Damage
- Intake Air Duct - Loose/Poor Connection/Restrictions/Visible Damage
- Intake Manifold - Vacuum leak
- Mechanical Condition @ Engine - Altered air flow
  For example:
  - Exhaust Port or Intake Port @ Cylinder Head - Casting Flash/Restrictions
  - Exhaust Valve or Intake Valve - Leaking/Stuck
  - Intake Manifold - Casting Flash/Restrictions/Vacuum leak
- Positive Crankcase Ventilation System - Dirty/Leaking/Poor Connection/Restricted - Refer to: Crankcase Ventilation System Inspection/Diagnosis
- Vacuum Hoses - Incorrect connection/Kinked/Leaking/Restricted
- If a condition exists
  Repair or replace as necessary
- Go to next step: If no condition exists
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
  A condition with the system still exists - Refer to: Step 3
- Go to next step: If the DTC is not set
All OK.