2010 Cadillac CTS Sedan AWD V6-3.6L Page 925
P0031, P0037, P0051, and P0057
The ECM detects a short to ground in the heater circuits of the HO2S when the heater is commanded OFF. The condition exists for greater than 4
seconds or a cumulative of 30 seconds.
P0032, P0038, P0052, and P0058
The ECM detects a short to voltage in the heater circuits of the HO2S when the heater is commanded ON. The condition exists for greater than 4
seconds or a cumulative of 30 seconds.
Action Taken When the DTC Sets
DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0056, P0057, and P0058 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0056, P0057, and P0058 are Type B DTCs.
Diagnostic Aids
* If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool Circuit
Test Status parameters for the component. The circuit status parameters change from OK or Not Run to Fault if there is a condition with the
circuit or a connection.
* An open fuse in the HO2S heater circuit may be caused by the heater element in one of the sensors. The condition may not be present until
the sensor operates for a period of time. If no fault is present in the heater circuit, monitor the amperage of each heater using the DMM to
determine if one of the heater elements is the cause of the open fuse. Inspect the sensor pigtail or the harness for contacting the exhaust
system.
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 at operating temperature for at least 30 seconds. Observe the DTC information, DTCs P0030, P0031, P0032, P0036, P0037,
P0038, P0050, P0051, P0052, P0056, P0057, and P0058 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 heated oxygen sensor (HO2S).
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal D and ground.
Note: The ignition circuit supplies voltage to other components. Make sure you test all circuits for a short to ground or test all components
for being shorted that share the ignition circuit.
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.