GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2006 🢒 VUE - AWD 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 DTC P0137 or P0157

Circuit Description

The secondary heated oxygen sensor (HO2S) measures the oxygen content of the exhaust downstream of the three-way catalyst (TWC), so that the TWC efficiency is optimized. The powertrain control module (PCM) supplies a voltage near 450 mV between the HO2S signal circuit and the low reference circuit. The HO2S varies the voltage over a range from about 1,000 mV when the exhaust is rich, down through about 10 mV when the exhaust is lean.

The PCM monitors and stores the HO2S voltage information. The PCM evaluates the HO2S voltage samples in order to determine the amount of time that the HO2S voltage was out of range. The PCM compares the stored HO2S voltage samples taken within each sample period and determines if the majority of the samples are out of the operating range.

The PCM monitors the HO2S voltage for being fixed below a predetermined voltage. If the PCM detects the voltage is too low, this DTC sets.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC P0137 HO2S Circuit Low Voltage Bank 1 Sensor 2
    • DTC P0157 HO2S Circuit Low Voltage Bank 2 Sensor 2

Conditions for Running the DTC
    • DTCs P0030, P0050, P0107, P0108, P0112, P0113, P0117, P0118, P0133, P0135, P0138, P0141, P0153, P0155, P0158, P0161, P0171, P0172, P0174, P0175, P0300, P0301-P0306, P0335, P0401, P0404, P0442, P0443, P0496, P1128, P1129, P2413, P2414, and P2415 are not set.
    • The engine is operating for more than 2 minutes.
    • The engine speed is less than 2,350 RPM.
    • The engine coolant temperature (ECT) is more than 69°C (156°F).
    • The intake air temperature (IAT) is more than -18°C (0°F).
    • The HO2S 1 same bank lambda is between 0.73-1.47.
    • The fuel system is in closed loop.
    • DTCs P0137 and P0157 run once per drive cycle when the above conditions are met.

Conditions for Setting the DTC
    • The PCM detects that the affected HO2S 2 signal voltage is less than 290 mV.
    • The condition exists for less than 45 seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

Conditions for Clearing the MIL/DTC
    • The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Use a scan tool in order to clear the MIL and the DTC.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Important: 

   • DTC P0137 is for bank 1 sensor 2 and DTC P0157 is for bank 2 sensor 2.
   • Inspect the heated oxygen sensor (HO2S) 2 for being secure before proceeding with this DTC. A sensor that is loose could cause this DTC to set.

  1. Allow the engine to reach operating temperature.
  2. Operate the engine above 1,200 RPM for 2 minutes.
  3. Observe the appropriate HO2S 2 voltage parameter with a scan tool.

Is the voltage less than the specified value?

290 mV

Go to Step 4

Go to Step 3

3
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

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Go to Step 4

Go to Intermittent Conditions

4

  1. Turn OFF the ignition.
  2. Disconnect the appropriate HO2S 2.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage between the HO2S 2 signal circuit and a good ground with a DMM.

Is the voltage more than the specified value?

100 mV

Go to Step 6

Go to Step 5

5
  1. Turn OFF the ignition.
  2. Disconnect the powertrain control module (PCM) connector.
  3. Test the appropriate HO2S 2 signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 7

6

Test shorted terminals and for poor connections at the HO2S. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 8

7

Test shorted terminals and for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

8

Replace the appropriate HO2S. Refer to the appropriate procedure:

Did you complete the replacement?

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Go to Step 10

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9
  1. Replace the PCM. Refer to Control Module References for replacement, setup, and programming.
  2. Perform the idle learn procedure. Refer to Idle Learn .

Did you complete the replacement?

--

Go to Step 10

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10
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

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Go to Step 2

Go to Step 11

11

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

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Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK