2010 Cadillac CTS Sedan AWD V6-3.6L Page 1062
Conditions for Clearing the MIL/DTC
DTCs P0131 and P0151 are Type B DTCs.
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 Verification
1. Engine idling, observe the appropriate scan tool HO2S 1 voltage parameter. The voltage should fluctuate above and below the range of
350-550 mV.
2. 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.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the appropriate HO2S 1.
2. Ignition ON, verify that the scan tool HO2S 1 voltage parameter is between 350-500 mV.
瀚慖f less than the specified range, test the signal circuit terminal B for a short to ground. If the circuit/connections test normal, replace the
ECM.
瀚慖f greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit/connections test normal, replace
the ECM.
3. Install a 3 A fused jumper wire between the signal circuit terminal B and ground. Verify the HO2S voltage parameter is less than 60 mV.
瀚慖f greater than the specified range, test the signal circuit for an open/high resistance. If the circuit/connections test normal, replace the
ECM.
4. Connect a 3 A fused jumper wire between the signal circuit terminal B and the low reference circuit terminal A. Verify the HO2S voltage
parameter is less than 60 mV.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance or for a short to voltage. If the
circuit/connections test normal, replace the ECM.
5. Verify that the following conditions do not exist:
* Lean condition.
* Low fuel system pressure-Refer to Fuel System Diagnosis (See: Powertrain Management/Computers and Control Systems/Testing and
Inspection/Component Tests and General Diagnostics/Fuel System Diagnosis).
* Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) (See: Powertrain
Management/Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (without Special
Tool) (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool)).
* Exhaust leaks near the HO2S.
* Engine vacuum leaks.
