2010 Cadillac CTS Sedan AWD V6-3.6L Page 1087
Action Taken When the DTC Sets
DTCs P0135, P0141, P0155, and P0161 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0135, P0141, P0155, and P0161 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
Note: It may take up to 8 minutes for the DTC to set.
1. With the engine at normal operating temperature, operate the engine above 1,200 RPM for 2 minutes and then allow the engine to idle. DTCs
P0135, P0141, P0155, or P0161 should not set.
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.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal C and ground.
瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and
the ignition circuit fuse is open, test all the components connected to the ignition circuit and replace as necessary.
3. Ignition OFF, connect a test lamp between the heater control circuit terminal D and B+. The test light should not illuminate.
瀚慖f the test lamp illuminates, test the heater control circuit for a short to ground. If the circuit/connections test normal, replace the ECM.
4. Idle the engine, verify the test lamp illuminates or flashes.
瀚慖f the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit/connections test normal, replace the ECM.
Note: The control circuit for the HO2S heater is pulled-up to voltage within the ECM, 2.0-3.0 V on the control circuit is normal.
5. Ignition ON, test for 2.0-3.0 V between the control circuit terminal D and ground.
瀚慖f not within the specified range, test the control circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.
6. If all circuits/connections test normal, test or replace the HO2S.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate HO2S.
2. Test for 5-25 ohm between terminals C and D of the HO2S.
