2010 Cadillac Truck SRX FWD V6-3.0L Page 2037
* The mass air flow (MAF) is between 4-13 g/s.
* The vehicle speed is between 64-125 km/h (40-78 mph).
* The fuel level is greater than 10 %.
* The fuel system is in Closed Loop.
* The predicted catalytic converter temperature is between 615-980掳C (1,139-1,796掳F).
* The HO2S heater is ON for more than 180 s.
* The DTCs run once per ignition cycle, during decel fuel cut-off, when the above conditions are met.
Conditions for Setting the DTC
P2271
The ECM does not detect an HO2S voltage less than 100 mV before accumulated mass air flow exceeds 36 grams.
P2273
The ECM does not detect an HO2S voltage less than 100 mV before the accumulated mass air flow exceeds 36 grams.
Action Taken When the DTC Sets
DTCs P2271 or P2273 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P2271 or P2273 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LAU) (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/Connector End Views By Name)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
* Heated Oxygen Sensor Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical
Diagnostic Procedures/Wiring Repairs/Heated Oxygen Sensor 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. Ignition ON, observe the DTC information with a scan tool. Verify no B52 HO2S heater DTCs are set.
瀚慖f a B52 HO2S heater DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
2. Engine running, observe the appropriate scan tool B52 HO2S voltage parameter. The reading should be within the range of 50-1,050 mV.
3. 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 appropriate B52 HO2S harness connector.
2. Ignition ON, observe the appropriate scan tool HO2S voltage parameter. The parameter should display 1.27 V.
