GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Captiva Sport 🢒 Engine 🢒 Engine Controls and Fuel - 2.8L, 3.0L, 3.2L, or 3.6L 🢒 DTC P0050, P0056, P0059, P0060, P0155, or P0161

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0050: HO2S Heater Control Circuit Bank 2 Sensor 1

DTC P0056: HO2S Heater Control Circuit Bank 2 Sensor 2

DTC P0059: HO2S Heater Resistance Bank 2 Sensor 1

DTC P0060: HO2S Heater Resistance Bank 2 Sensor 2

DTC P0155: HO2S Heater Performance Bank 2 Sensor 1

DTC P0161: HO2S Heater Performance Bank 2 Sensor 2

Diagnostic Fault Information

HO2S Heater Bank 2 Sensor 1

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

HO2S Heater Voltage Supply

Opens fuse

P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P0102, P0134, P0135, P0140, P0141, P0154, P0155, P0160, P0161, P0443, P0480, P0481, P0645

P0050, P0059, P0155

P0050, P0059, P0155

P0690

P0155

HO2S Heater Low Control

P0050, P0155

P0050, P0059, P0155

P0050, P0059, P0155

P0050, P0155, P0690

P0155


HO2S Heater Bank 2 Sensor 2

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

HO2S Heater Voltage Supply

Opens fuse

P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P0102, P0134, P0135, P0140, P0141, P0154, P0155, P0160, P0161, P0443, P0480, P0481, P0645

P0056, P0060, P0161

P0056, P0060, P0161

P0056, P0161, P0690

P0161

HO2S Heater Low Control

P0050, P0056

P0056, P0060, P0160

P0056, P0060, P0161

P0056, P0161, P0690

P0161

Typical Scan Tool Data

HO2S Heater Bank 2 Sensor 1

Circuit

Normal Range

Short to Ground

Open

Short to Voltage

HO2S Heater Voltage Supply

Approximately 0.5-2 A

0.00 A

0.00 A

Approximately 0.5-2 A

HO2S Heater Voltage Supply

7-100%

7%

7%

7-100%

HO2S Heater Low Control

Approximately 0.5-2 A

0.00 A

0.00 A

0.00 A

HO2S Heater Low Control

7-100%

7%

7%

7%


HO2S Heater Bank 2 Sensor 2

Circuit

Normal Range

Short to Ground

Open

Short to Voltage

HO2S Heater Voltage Supply

Approximately 0.5-2 A

0.00 A

0.00 A

Approximately 0.5-2 A

HO2S Heater Voltage Supply

7-100%

7%

7%

7-100%

HO2S Heater Low Control

Approximately 0.5-2 A

0.00 A

0.00 A

0.00 A

HO2S Heater Low Control

7-100%

7%

7%

7%

Circuit/System Description

Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by an ignition voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the engine control module (ECM). The ECM uses pulse width modulation (PWM) to control the HO2S heater operation to maintain a specific HO2S operating temperature range.

Conditions for Running the DTC

P0050 and P0056

    • The engine is cranking or running.
    • The Engine Speed parameter is greater than 400 RPM.
    • The system voltage is between 10-18 volts.

P0059 and P0060

    • DTCs P0112, P0113, P0116, P0117, P0118, P0128, P1258, P2610 are not set.
    • The ignition is OFF for more than 8 hours.
    • The difference between the start-up engine coolant temperature (ECT) and the intake air temperature (IAT) is less than 8°C (14.4°F).
    • The ECT Sensor parameter is between -30 and +45°C (-22 and +133°F) at engine start-up.
    • The system voltage is between 10-18 volts.
    • This diagnostic runs one time per valid cold start when the above conditions are met.

P0155

    • DTCs P0050, P0059, P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
    • The system voltage is between 10-18 volts.
    • The scan tool special functions are not active.
    • The Engine Run Time parameter is more than 180 seconds.
    • The ECT Sensor parameter is at least 65°C (149°F).
    • The Engine Speed parameter is between 500-3,000 RPM.
    • The MAF sensor parameter is between 5-30 g/s.
    • The above conditions have been met for more than 2 seconds.

P0161

    • DTCs P0056, P0060, P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
    • The system voltage is between 10-18 volts.
    • The scan tool special functions are not active.
    • The Engine Run Time parameter is at least 180 seconds.
    • The ECT parameter is at least 65°C (149°F).
    • The Engine Speed parameter is between 500-3,000 RPM.
    • The MAF Sensor parameter is between 5-30 g/s.
    • The above conditions have been met for more than 2 seconds.

Conditions for Setting the DTC

P0050 and P0056

    • The ECM detects that the HO2S heater control circuit status is incorrect for more than 2 seconds.
    • This diagnostic runs continuously.

P0059

The ECM detects that the HO2S heater calculated resistance is not between 1.3-7.5 ohms at engine start-up for 1 second.

P0060

The ECM detects that the HO2S heater calculated resistance is not between 1.9-8.6 ohms at engine start-up for 1 second.

P0155

    • The HO2S heater current is less than 0.25 amp or more than 3.13 amps for more than 8 seconds, twice in a 1-minute period.
    • The test is run 2 times per trip.

P0161

    • The HO2S heater current is less than 0.43 amp or more than 2.90 amp for more than 8 seconds, twice within a 1-minute test period.
    • The test is run 2 times per trip.

Action Taken When the DTC Sets

DTCs P0050, P0056, P0059, P0060, P0155, and P0161 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0050, P0056, P0059, P0060, P0155, and P0161 are Type B DTCs.

Diagnostic Aids

When using a high impedance, low current draw, test lamp to load the heater circuit, the test lamp flash may be dim, the scan tool Heater Command parameter may indicate 7 percent, and the Heater parameter may indicate 0.00 amps. This is a normal condition.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs
    •  Heated Oxygen Sensor Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Allow the engine to reach operating temperature.
  2. Engine running, verify the appropriate scan tool HO2S Heater parameter is varying between 0.5-2 amp.
  3. 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

Important:  You must perform the Circuit/System Verification before proceeding with 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 appropriate HO2S heater voltage supply circuit terminal D and ground.
    3. ⇒If the test lamp does not illuminate, test the HO2S heater voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the HO2S heater voltage supply circuit fuse is open, test all components connected to the fuse and replace as necessary.
  3. Ignition ON, verify that a test lamp does not illuminate between the appropriate HO2S heater voltage supply circuit terminal D and the appropriate HO2S heater low control circuit terminal listed below:
    4. • B2S1 terminal C
    • B2S2 terminal E
    ⇒If the lamp illuminates, test the HO2S heater low control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  4. Engine running, leave the test lamp connected from the previous step. The lamp should flash or be ON steady.
    5. ⇒If the test lamp is not ON steady or flashing, test the HO2S heater low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

    Important: 

       • The output driver should detect a short to voltage and turn OFF. If a resistance fault is present the driver will remain ON and the scan tool will display more than 0.0 amp. Less than 10 ohms of resistance may set a DTC.
       • Performing this test may set additional DTCs.

  5. Ignition OFF, install a 30A fused jumper wire between the appropriate HO2S heater voltage supply circuit terminal D and the appropriate HO2S heater low control circuit terminal listed below:
    6. • B2S1 terminal C
    • B2S2 terminal E
  6. Engine running, verify the appropriate scan tool HO2S Heater parameter is less than 0.1 amp.
    7. ⇒If more than the specified range, test the HO2S heater voltage supply and HO2S heater low control circuits for more than 1 ohm of resistance. If the circuits test normal, replace the ECM.
  7. If the ECM and all circuits test normal, replace the appropriate HO2S.

Repair Instructions

Notice: Refer to Heated Oxygen Sensor Resistance Learn Reset Notice in the Preface section.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Heated Oxygen Sensor Replacement - Bank 2 Sensor 1
    •  Heated Oxygen Sensor Replacement - Bank 2 Sensor 2
    •  Control Module References for ECM replacement, setup, and programming

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0050: HO2S Heater Control Circuit Bank 2 Sensor 1

DTC P0056: HO2S Heater Control Circuit Bank 2 Sensor 2

DTC P0059: HO2S Heater Resistance Bank 2 Sensor 1

DTC P0060: HO2S Heater Resistance Bank 2 Sensor 2

DTC P0155: HO2S Heater Performance Bank 2 Sensor 1

DTC P0161: HO2S Heater Performance Bank 2 Sensor 2

Diagnostic Fault Information

HO2S Heater Bank 2 Sensor 1

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

HO2S Heater Voltage Supply

Opens fuse

P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P0102, P0134, P0135, P0140, P0141, P0154, P0155, P0160, P0161, P0443, P0480, P0481, P0645

P0050, P0059, P0155

P0050, P0059, P0155

P0690

P0155

HO2S Heater Low Control

P0050, P0155

P0050, P0059, P0155

P0050, P0059, P0155

P0050, P0155, P0690

P0155


HO2S Heater Bank 2 Sensor 2

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

HO2S Heater Voltage Supply

Opens fuse

P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P0102, P0134, P0135, P0140, P0141, P0154, P0155, P0160, P0161, P0443, P0480, P0481, P0645

P0056, P0060, P0161

P0056, P0060, P0161

P0056, P0161, P0690

P0161

HO2S Heater Low Control

P0050, P0056

P0056, P0060, P0160

P0056, P0060, P0161

P0056, P0161, P0690

P0161

Typical Scan Tool Data

HO2S Heater Bank 2 Sensor 1

Circuit

Normal Range

Short to Ground

Open

Short to Voltage

HO2S Heater Voltage Supply

Approximately 0.5-2 A

0.00 A

0.00 A

Approximately 0.5-2 A

HO2S Heater Voltage Supply

7-100%

7%

7%

7-100%

HO2S Heater Low Control

Approximately 0.5-2 A

0.00 A

0.00 A

0.00 A

HO2S Heater Low Control

7-100%

7%

7%

7%


HO2S Heater Bank 2 Sensor 2

Circuit

Normal Range

Short to Ground

Open

Short to Voltage

HO2S Heater Voltage Supply

Approximately 0.5-2 A

0.00 A

0.00 A

Approximately 0.5-2 A

HO2S Heater Voltage Supply

7-100%

7%

7%

7-100%

HO2S Heater Low Control

Approximately 0.5-2 A

0.00 A

0.00 A

0.00 A

HO2S Heater Low Control

7-100%

7%

7%

7%

Circuit/System Description

Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by an ignition voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the engine control module (ECM). The ECM uses pulse width modulation (PWM) to control the HO2S heater operation to maintain a specific HO2S operating temperature range.

Conditions for Running the DTC

P0050 and P0056

    • The engine is cranking or running.
    • The Engine Speed parameter is greater than 400 RPM.
    • The system voltage is between 10-18 volts.

P0059 and P0060

    • DTCs P0112, P0113, P0116, P0117, P0118, P0128, P1258, P2610 are not set.
    • The ignition is OFF for more than 8 hours.
    • The difference between the start-up engine coolant temperature (ECT) and the intake air temperature (IAT) is less than 8°C (14.4°F).
    • The ECT Sensor parameter is between -30 and +45°C (-22 and +133°F) at engine start-up.
    • The system voltage is between 10-18 volts.
    • This diagnostic runs one time per valid cold start when the above conditions are met.

P0155

    • DTCs P0050, P0059, P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
    • The system voltage is between 10-18 volts.
    • The scan tool special functions are not active.
    • The Engine Run Time parameter is more than 180 seconds.
    • The ECT Sensor parameter is at least 65°C (149°F).
    • The Engine Speed parameter is between 500-3,000 RPM.
    • The MAF sensor parameter is between 5-30 g/s.
    • The above conditions have been met for more than 2 seconds.

P0161

    • DTCs P0056, P0060, P0068, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0451, P0452, P0453, P0454, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
    • The system voltage is between 10-18 volts.
    • The scan tool special functions are not active.
    • The Engine Run Time parameter is at least 180 seconds.
    • The ECT parameter is at least 65°C (149°F).
    • The Engine Speed parameter is between 500-3,000 RPM.
    • The MAF Sensor parameter is between 5-30 g/s.
    • The above conditions have been met for more than 2 seconds.

Conditions for Setting the DTC

P0050 and P0056

    • The ECM detects that the HO2S heater control circuit status is incorrect for more than 2 seconds.
    • This diagnostic runs continuously.

P0059

The ECM detects that the HO2S heater calculated resistance is not between 1.3-7.5 ohms at engine start-up for 1 second.

P0060

The ECM detects that the HO2S heater calculated resistance is not between 1.9-8.6 ohms at engine start-up for 1 second.

P0155

    • The HO2S heater current is less than 0.25 amp or more than 3.13 amps for more than 8 seconds, twice in a 1-minute period.
    • The test is run 2 times per trip.

P0161

    • The HO2S heater current is less than 0.43 amp or more than 2.90 amp for more than 8 seconds, twice within a 1-minute test period.
    • The test is run 2 times per trip.

Action Taken When the DTC Sets

DTCs P0050, P0056, P0059, P0060, P0155, and P0161 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0050, P0056, P0059, P0060, P0155, and P0161 are Type B DTCs.

Diagnostic Aids

When using a high impedance, low current draw, test lamp to load the heater circuit, the test lamp flash may be dim, the scan tool Heater Command parameter may indicate 7 percent, and the Heater parameter may indicate 0.00 amps. This is a normal condition.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs
    •  Heated Oxygen Sensor Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Allow the engine to reach operating temperature.
  2. Engine running, verify the appropriate scan tool HO2S Heater parameter is varying between 0.5-2 amp.
  3. 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:  You must perform the Circuit/System Verification before proceeding with 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 appropriate HO2S heater voltage supply circuit terminal D and ground.
    3. ⇒If the test lamp does not illuminate, test the HO2S heater voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal and the HO2S heater voltage supply circuit fuse is open, test all components connected to the fuse and replace as necessary.
  3. Ignition ON, verify that a test lamp does not illuminate between the appropriate HO2S heater voltage supply circuit terminal D and the appropriate HO2S heater low control circuit terminal listed below:
    4. • B2S1 terminal C
    • B2S2 terminal E
    ⇒If the lamp illuminates, test the HO2S heater low control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  4. Engine running, leave the test lamp connected from the previous step. The lamp should flash or be ON steady.
    5. ⇒If the test lamp is not ON steady or flashing, test the HO2S heater low control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

    Note: 

       • The output driver should detect a short to voltage and turn OFF. If a resistance fault is present the driver will remain ON and the scan tool will display more than 0.0 amp. Less than 10 ohms of resistance may set a DTC.
       • Performing this test may set additional DTCs.

  5. Ignition OFF, install a 30A fused jumper wire between the appropriate HO2S heater voltage supply circuit terminal D and the appropriate HO2S heater low control circuit terminal listed below:
    6. • B2S1 terminal C
    • B2S2 terminal E
  6. Engine running, verify the appropriate scan tool HO2S Heater parameter is less than 0.1 amp.
    7. ⇒If more than the specified range, test the HO2S heater voltage supply and HO2S heater low control circuits for more than 1 ohm of resistance. If the circuits test normal, replace the ECM.
  7. If the ECM and all circuits test normal, replace the appropriate HO2S.

Repair Instructions

Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution in the Preface section.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Heated Oxygen Sensor Replacement - Bank 2 Sensor 1
    •  Heated Oxygen Sensor Replacement - Bank 2 Sensor 2
    •  Control Module References for ECM replacement, setup, and programming