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GM Master Tech 01
GM Master Tech 01, GM Master Technician
Category: Chevy
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Experience:  GM certified master technician 10 years experience
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2001 suburban: my service engine soon light came..passanger..o2

Customer Question

on my 2001 suburban my service engine soon light came on and i have an error code P1153. is that that the passanger o2 downstream sensor? by the way i just had the dealer replace the cat converter system 2 weeks ago then this light came on a week later. thank you
Submitted: 9 years ago.
Category: Chevy
Expert:  GM Master Tech 01 replied 9 years ago.

This diagnostic applies only to vehicles built with Delphi heated oxygen sensors. To identify the heated oxygen sensor refer to Delphi/Denso Sensor in Computers and Control Systems Component Views.

The Powertrain Control Module (PCM) monitors the Heated Oxygen Sensor (HO2S) activity for 100 seconds . During this monitor period the PCM counts the number of times that the HO2S switches from rich to lean and lean to rich. A DTC P1133 or P1153 sets when the PCM determines that the HO2S did not switch enough times.

A lean to rich switch is determined when the HO2S voltage changes from less than 300 mV to more than 600 mV . A rich to lean switch is determined when the HO2S voltage changes from more than 600 mV to less than 300 mV .


  • DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0200, P0300, P0401, P0404, P0405, P0410, P0440, P0442, P0446, P0452, P0453, P1120, P1125, P1220, P1221, P1258, P1404, P1415, P1416, P1514, P1515, P1516, P1517, or P1518 are not set.
  • The Engine Coolant Temperature (ECT) is more than 65°C (149°F) .
  • The engine run time is more than 160 seconds .
  • The EVAP purge solenoid command is more than 0 percent .
  • The Mass Air Flow (MAF) is between 2-50 g/s .
  • The engine speed is between 1,200-3,000 RPM .
  • Vehicles without Throttle-actuated Control (TAC) , the Throttle Position (TP) is more than 5 percent .
  • Vehicles with Throttle-actuated Control (TAC), the Throttle Position (TP) indicated angle is 5 percent more than the value observed at idle.
  • The loop status is closed.
  • The ignition 1 signal is between 9-18 volts .
  • The fuel tank level remaining is more than 10 percent .
  • Intrusive tests are not in progress.
  • The scan tool output controls are not active.

The HO2S lean-to-rich and rich-to-lean switches are less than a calibrated value for 100 seconds .


  • The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
  • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.


  • The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
  • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
  • 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.


IMPORTANT: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.

  • Inspect the HO2S high signal circuit for being shorted to a PCM ground. The HO2S high signal circuit shorted to a PCM ground sets a switching DTC.
  • A malfunction in the HO2S heater circuits will cause a DTC P1133 or P1153 to set. Check HO2S heater circuits for intermittent opens/connections.
  • An oxygen supply inside the HO2S is necessary for proper operation. This supply of oxygen is provided through the HO2S wires. All HO2S wires and connections should be inspected for breaks or contamination. Refer to Heated Oxygen Sensor (HO2S) Wiring Repairs in Diagrams.
  • Using the Freeze Frame/Failure Records data may help to locate an intermittent condition. If you cannot duplicate the DTC, use the Freeze Frame/Failure Records in order to determine how many miles since the DTC set. You can also use the Fail Counter and the Pass Counter in order to determine how many ignition cycles the diagnostic reported a pass and/or a fail. In order to isolate when the DTC failed, operate vehicle within the same freeze frame conditions that you observed:
  • The RPM
  • The vehicle load
  • The vehicle speed
  • The temperature

For an intermittent, Refer to Intermittent Conditions. See: Symptom Related Diagnostic Procedures\Intermittent Conditions


Steps 1-7

Steps 8-15

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if the fault is present. This test may take 5 minutes for the diagnostic to run. For any test that requires probing the PCM or a component harness connector, use the connector test adapter kit. Using this kit prevents damage to the harness connector terminals.
  2. When DTCs P1133 and P1153 are set at the same time, this is a good indication that a fuel contamination condition is present.
  3. An exhaust leak 6-12 inches away from the HO2S can cause a DTC to set.
  4. This step tests the HO2S for being tight and the connectors and circuits are OK.
  5. This step tests the integrity of the HO2S low signal circuit to the PCM.
  6. This step tests the integrity of the signal circuit to the PCM.