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 DTC P0030, P0031, P0032, P0050, P0051, P0052, P0135, P0155 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
Engine - Idling - At normal operating temperature.
Verify the scan tool parameter: Heated Oxygen Sensor or Heated Oxygen Sensor 2 = Between Lambda 0.8 and 1.1 & Fluctuates
- If not between 0.8 and 1.1 or does not fluctuate
  Refer to: Circuit/System Testing
- Go to next step: If between 0.8 and 1.1 and fluctuates
Verify the scan tool parameter: Heated Oxygen Sensor or Heated Oxygen Sensor 2 = Between Lambda 0.8 and 1.1 & Fluctuates
Perform the action while monitoring the parameter:
- Wiggle the harness and connector: B52 Heated Oxygen Sensor
- Wiggle the harness and connector: K20 Engine Control Module
- If not between 0.8 and 1.1 or does not fluctuate
  Repair as necessary - Wiring / Terminal (s) / Electrical Connector (s)
- Go to next step: If between 0.8 and 1.1 and fluctuates
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
  Refer to: Circuit/System Testing
- Go to next step: If the DTC is not set
All OK.