P0133

DTC P0133 or P0153

Circuit Description

The powertrain control module (PCM) continuously monitors the heated oxygen sensor (HO2S) activity for 60 seconds. During the monitor period the PCM counts the number of times that the HO2S responds from rich to lean and from lean to rich, and adds the amount of time that was needed to complete all transitions. With this information, the PCM can determine the average time for all transitions. It the average response time is too slow, a DTC will set. The PCM determines the lean to rich transition when the HO2S voltage changes from less than 300 mV to more than 600 mV. The PCM determines the rich to lean transition when the HO2S voltage changes from more than 600 mV to less than 300 mV. An HO2S that responds too slowly will set this DTC.


DTC Descriptors

This diagnostic procedure supports the following DTCs.

- DTC P0133 HO2S Slow Response Bank 1 Sensor 1

- DTC P0153 HO2S Slow Response Bank 2 Sensor 1


Conditions for Running the DTC

- DTCs P0101, P0102, P0103, P0106, P0107, P0108 P0112, P0113. P0116, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0131, P0132, P0134, P0135, P0151, P0152, P0154, P0155, P0200, P0300, P0443, P0496, P1111, P1112, P1114, P1115, P1121, or P1122 are not set.

- The engine coolant temperature (ECT) is more than 60°C (140°F).

- The ignition 1 signal is between 10-18 volts.

- The loop status is CLOSED.

- The engine speed between 1,200-3,000 RPM.

- The engine air flow is between 20-55 grams per second.

- The evaporative emission (EVAP) purge solenoid is more than 0 percent.

- The engine run time is more than 160 seconds.

- The throttle position (TP) is more than 5 percent.

- The fuel tank level remaining is more than 10 percent.

- DTC P0133 and P0153 run once per ignition cycle when the above conditions are met.


Conditions for Setting the DTC

- The lean to rich response, defined as less than 250 mV to more than 625 mV, average time is more than 255 ms.

- The rich to lean response, defined as more than 625 mV to less than 250 mV, average time is more than 255 ms.

Action Taken When the DTC Sets

- 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.


Conditions for Clearing the MIL/DTC

- 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.

- Clear the MIL and the DTC with a scan tool.


Test Description

DTC P0133 or P0153 Steps 1-8:

DTC P0133 or P0153 Steps 9-15:

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

2. This step determines if the fault is present. This test may take 5 minutes for the diagnostic to run.

3. When DTCs P0133 and P0153 are set at the same time, a fuel contamination condition is probably present.

4. An exhaust leak 15.2-30.1 cm (6-12 inches) away from the HO2S can cause a DTC to set.

5. This step verifies whether a good ground circuit is available.

6. This step verifies the integrity of the HO2S low signal circuit to the PCM.

7. This step verifies the integrity of the HO2S high signal circuit to the PCM

8. Certain RTV silicone gasket materials release vapors that can contaminate the HO2S. Silicone in the fuel can also cause silicone contamination. If the sensors appear silicone-contaminated, and if and all the silicone sealant is a non-silicone base, advise the customer to try a different fuel company. A missing fuel filler restrictor indicates the customer may have used leaded fuel.