P0160
DTC P0131, P0132, P0134, P0137, P0138, P0140, P0151, P0152, P0154, P0157, P0158, or P0160
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0131
- HO2S Circuit Low Voltage Bank 1 Sensor 1
DTC P0132
- HO2S Circuit High Voltage Bank 1 Sensor 1
DTC P0134
- HO2S Circuit High Voltage Bank 1 Sensor 1
DTC P0137
- HO2S Circuit Low Voltage Bank 1 Sensor 2
DTC P0138
- HO2S Circuit High Voltage Bank 1 Sensor 2
DTC P0140
- HO2S Circuit Insufficient Activity Bank 1 Sensor 2
DTC P0151
- HO2S Circuit Low Voltage Bank 2 Sensor 1
DTC P0152
- HO2S Circuit High Voltage Bank 2 Sensor 1
DTC P0154
- HO2S Circuit Insufficient Activity Bank 2 Sensor 1
DTC P0157
- HO2S Circuit Low Voltage Bank 2 Sensor 2
DTC P0158
- HO2S Circuit High Voltage Bank 2 Sensor 2
DTC P0160
- HO2S Circuit Insufficient Activity Bank 2 Sensor 2
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream. When the engine is started, the control module operates in an Open Loop mode, ignoring the HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a range of 0-1,000 mV. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1,000 mV indicates a rich fuel mixture. An HO2S voltage that decreases toward 0 mV indicates a lean fuel mixture.
The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed Loop earlier and the control module to calculate the air-to-fuel ratio sooner.
Conditions for Running the DTC
P0131, P0137, P0151, or P0157
* DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
* The engine is operating in Closed Loop.
* The Ignition voltage is between 10-32 V.
* The fuel level is greater than 10 percent.
* The throttle position (TP) is between 3-70 percent.
* The DTCs run continuously when the above conditions are met for 2 s.
P0132, P0138, P0152, or P0158
* DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
* The engine is operating in Closed Loop.
* The Ignition voltage is between 10-32 V.
* The fuel level is greater than 10 percent.
* The throttle position (TP) is between 0-70 percent.
* The DTCs run continuously when the above conditions are met for 3 s.
P0134, P0140, P0154, or P0160
* DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
* The ignition voltage is between 10-32 V.
* The engine run time is greater than 150 s.
* The fuel system is in Closed Loop.
* The DTCs run continuously when the above conditions are met.
Conditions for Setting the DTC
P0131, P0137, P0151, or P0157
* The ECM detects that the HO2S voltage is less than 50 mV.
* The DTCs set within 50 s when the above condition is met.
P0132, P0138, P0152, or P0158
* The ECM detects that the HO2S voltage is greater than 1,050 mV.
* The DTCs set within 50 s when the above condition is met.
P0134 or P0154
* The ECM detects that the HO2S 1 voltage is between 350-550 mV.
* The HO2S heater warm-up cycle is complete.
* The DTCs set within 15 s when the above conditions are met.
P0140 or P0160
* The ECM detects that the HO2S 2 voltage is not varying.
* The HO2S heater warm-up cycle is complete.
* The DTCs set within 15 s when the above conditions are met.
Action Taken When the DTC Sets
DTCs P0131, P0132, P0134, P0137, P0138, P0140, P0151, P0152, P0154, P0157. P0158, and P0160 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0131, P0132, P0134, P0137, P0138, P0140, P0151, P0152, P0154, P0157, P0158, and P0160 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Connector Views
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON, observe the DTC information with a scan tool. Verify no HO2S heater DTCs are set.
• If a HO2S heater DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Engine running, observe the appropriate scan tool 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 1.9 V.
• If less than the specified range, test the high and low signal circuits for a short to ground. If both signal circuit test normal, replace the K20 ECM.
3. Ignition ON, test for 2.5-3.0 V between the high signal circuit terminal B and ground.
• If less than the specified range, test the high signal circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.
• If greater than the specified range, test the high signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
4. Ignition OFF, connect a 3 A fused jumper wire between the high signal circuit terminal B and the low signal circuit terminal A.
Note: The low signal circuit is tied to a pull-up circuit within the ECM. A voltage of 0.90-1.10 V on the low signal circuit is normal.
5. Ignition ON, verify the scan tool HO2S parameter displays 0.0 V.
• If greater than the specified range, test the low signal circuit for an open/high resistance or for a short to voltage. If the circuit tests normal, replace the K20 ECM.
6. Verify none of the following conditions exist:
* Water intrusion in the B52 HO2S harness connector
* Low or high fuel system pressure-Refer to Fuel System Diagnosis Fuel System Diagnosis.
* Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis Testing and Inspection.
* Fuel saturation of the evaporative emission (EVAP) canister
* Exhaust leaks
* Engine vacuum leaks
• If any of the above conditions exist, repair as necessary. If all circuits test normal, test or replace the appropriate B52 HO2S.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 Heated Oxygen Sensor Replacement - Bank 1 Sensor 1
* Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 Heated Oxygen Sensor Replacement - Bank 1 Sensor 2
* Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 Heated Oxygen Sensor Replacement - Bank 2 Sensor 1
* Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 Heated Oxygen Sensor Replacement - Bank 2 Sensor 2
* Perform the scan tool Heated Oxygen Sensor Resistance Learn Reset after replacing an HO2S.
* Control Module References Control Module References for ECM replacement, programming and setup.