P015B
DTC P015A or P015B (LUW)
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 provide an overview of each diagnostic category.
DTC Descriptors
DTC P015A
- HO2S Delayed Response Rich to Lean Bank 1 Sensor 1
DTC P015B
- HO2S Delayed Response Lean to Rich Bank 1 Sensor 1
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 0-1 275 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
P015A
* DTCs P0030, P0036, P0053, P0054, P0101, P0102, P0103, P0106, P0107, P0108, P0120, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0443, P1133, P1516, P2101, P2119, P2135, P2176, P2270, P2271, P2A00 are not set.
* The system voltage is between 11-32 V.
* The fuel level is more than 10%.
* Engine run time is equal to or more than 40 s.
* The engine coolant is hotter than 50.25°C (122.45°F).
Then
* Deceleration fuel cut-off is active
* The accelerator pedal position (APP) is stable
* The torque converter clutch (TCC) is locked
* DTC P013E and P2270 have run and passed.
* DTC P015A runs once per trip
P015B
* DTCs P0030, P0036, P0053, P0054, P0101, P0102, P0103, P0106, P0107, P0108, P0120, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0443, P1133, P1516, P2101, P2119, P2135, P2176, P2270, P2271, P2A00 are not set.
* The system voltage is between 11-32 V.
* The fuel level is more than 10%.
* Engine run time is equal to or more than 40 s.
* The engine coolant is hotter than 50.25°C (122.45°F).
Then
* DTCs P013A, P013E, P013F, P2270, and P2271 have run and passed.
* DTC P015B runs once per trip
Conditions for Setting the DTC
P015A
The ECM detects that the accumulated mass air flow monitored during rich to lean transitions between 550-775 mV is more than 15 g.
P015B
The ECM detects that the accumulated mass air flow monitored during rich to lean transitions between 550-775 mV is more than 15 g.
Action Taken When the DTC Sets
DTCs P015A and P015B are Type A DTCs.
Conditions for Clearing the DTC
DTCs P015A and P015B are Type A DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LUW) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left (D6I)
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. If any heated oxygen sensor (HO2S) heater DTCs are set, perform those diagnostics first.
2. Allow the engine to reach operating temperature.
3. Engine running, observe the affected heated oxygen sensor (HO2S) parameter with a scan tool.
* The heated oxygen sensor (HO2S) 1 value should vary from below 200 mV to above 800 mV and respond to fueling changes.
* The heated oxygen sensor (HO2S) 2 value should change more than 200 mV when the throttle is quickly cycled 3 times from closed to wide open and back to closed after running the engine at 1 500 RPM for 30 s.
Caution: Refer to Silicon Contamination of Heated Oxygen Sensors Caution Silicon Contamination of Heated Oxygen Sensors Caution.
4. The affected heated oxygen sensor (HO2S) may be damaged due to contamination. Prior to replacing the affected heated oxygen sensor (HO2S), inspect for the following sources of contamination:
* A silicon contaminated HO2S
* Fuel contamination, refer to Alcohol/Contaminants-in-Fuel Diagnosis Testing and Inspection.
* Engine oil consumption, refer to Oil Consumption Diagnosis Oil Consumption Diagnosis.
* Engine coolant consumption, refer to Loss of Coolant Loss of Coolant.
5. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
Circuit/System Testing
Note: All modules must be powered down or misdiagnosis may result.
1. Ignition OFF, disconnect the scan tool and wait 60 s to ensure all modules are powered down.
2. Disconnect the B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2 harness connector.
3. Measure for less than 5 ohm between B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2 low signal circuit terminal 3 and ground.
• If more than the specified range, test the appropriate B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2 low signal circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
4. Ignition ON, test for 1.5-2.1 V between the B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2 signal circuit terminal 4 and ground.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.
5. Install a 3 A fused jumper wire between the B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2 signal circuit terminal 4 and the low reference circuit terminal 3 of the appropriate B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2. Engine running, verify the scan tool HO2S parameter is less than 60 mV.
• If greater than the specified value, replace the K20 Engine Control Module.
6. Verify none of the following conditions exist:
* Water intrusion in the HO2S harness connector
* Low or high fuel system pressure, refer to Fuel System Description Fuel System Description.
* Fuel that is contaminated, refer to Alcohol/Contaminants-in-Fuel Diagnosis Testing and Inspection.
* Fuel saturation of the evaporative emission (EVAP) canister
* Exhaust leaks near the HO2S
* Engine vacuum leaks
• If you find any of the above conditions, repair as necessary.
7. If all circuits test normal, replace the B52A Heated Oxygen Sensor 1 or B52B Heated Oxygen Sensor 2.
Repair Instructions
Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution Heated Oxygen Sensor Resistance Learn Reset Caution.
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Heated Oxygen Sensor Replacement - Sensor 1 (LDE, LXV, LUW, 2H0) Heated Oxygen Sensor Replacement - Sensor 1
* Heated Oxygen Sensor Replacement - Sensor 2 Heated Oxygen Sensor Replacement - Sensor 2
* Control Module References Control Module References for ECM replacement, programming, and setup