2010 Cadillac CTS Sedan AWD V6-3.6L Page 1406
* A damaged oxygen sensor or wiring harness
Reference Information
Schematic Reference
Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics
(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
1. Observe the DTC information with a scan tool. Verify there are no HO2S, fuel system, or misfire DTCs set.
瀚慖f there are any of the DTCs set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) to diagnosis the applicable DTC before proceeding with this diagnostic
procedure.
2. Verify the following conditions do not exist with the catalytic converter:
* Dents
* A severe discoloration caused by excessive temperatures
* Road damage
* An internal rattle caused by damaged catalyst substrate
* Restrictions
瀚慖f a condition is found, repair as necessary.
3. Verify the following conditions do not exist with the exhaust system:
* Leaks
* Physical damage
* Loose or missing hardware
* Improperly torqued HO2S
瀚慖f a condition is found, repair the exhaust system.
4. Verify the following conditions do not exist with the HO2S 2:
* A grounded wiring harness
* Damage
瀚慖f a condition is found, replace the HO2S 2.
5. If no physical condition is detected and the HO2S 2 is as active as the HO2S 1 after operating the engine at 1,500 RPM for 1 minute and then
returning to a stabilized idle, then replace the catalytic converter
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Exhaust Leakage (See: Engine, Cooling and Exhaust/Exhaust System/Testing and Inspection/Exhaust Leakage)
* Restricted Exhaust (See: Engine, Cooling and Exhaust/Exhaust System/Testing and Inspection/Restricted Exhaust)
* Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (LF1) (See: Powertrain Management/Computers and Control Systems/Oxygen
