Without Oshawa Assembly

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Schematic:

CIRCUIT DESCRIPTION
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 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.

CONDITIONS FOR RUNNING THE DTC
^ No active Mass Air Flow (MAF) DTCs
^ No active Intake Air Temperature (IAT) DTCs
^ No active Engine Coolant Temperature (ECT) DTCs
^ No active Throttle Position (TP) DTCs
^ No active Injector DTCs
^ No active Crankshaft Position (CKP) sensor DTCs
^ No active Ignition Control (IC) DTCs
^ The fuel system is operating in Closed Loop.
^ The engine run time is more than 120 seconds.
^ The engine speed is between 1,200 RPM and 3,000 RPM.
^ The ignition voltage is more than 9 volts.
^ The ECT is more than 65°C (149°F).
^ The MAF is between 23 g/s and 50 g/s.
^ The Evaporative Emission (EVAP) purge duty cycle is more than 0 percent.

CONDITIONS FOR SETTING THE DTC
The PCM determines that within 100 seconds the HO2S lean to rich switches are less than 10 and rich to lean switches are less then 10.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
^ The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the 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.

DIAGNOSTIC AIDS

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

^ Inspect the HO2S signal circuit for being shorted to a PCM ground. The HO2S signal circuit shorted to a PCM ground sets a switching DTC.
^ A malfunction in the HO2S heater circuits will cause a DTC P1133 to set. Check HO2S heater circuits for intermittent opens or loose 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 and Failure Records data may aid in locating an intermittent condition. If the DTC cannot be duplicated, the information included in the Freeze Frame and Failure Records data can be useful in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also be used to determine how many ignition cycles the diagnostic reported a pass or a fail. Operate vehicle within the same Freeze Frame conditions, such as RPM, load, vehicle speed, temperature etc., that you observed. This will isolate when the DTC failed.

For an intermittent, refer to Symptoms. Symptom Related Diagnostic Procedures

TEST DESCRIPTION
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. 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.
3. When DTCs P1133 and P1153 are set at the same time, this is a good indication that a fuel contamination condition is present.
4. An exhaust leak 6-12 inches away from the HO2S can cause a DTC to set.
5. This step tests the HO2S for being tight and the connectors and circuits are OK.
6. This step tests the integrity of the HO2S low signal circuit to the PCM.
7. This step tests the integrity of the signal circuit to the PCM.
8. Certain room temperature vulcanizing (RTV) silicon gasket materials give off vapors that can contaminate the HO2S. There is also a possibility of silicon contamination caused by silicon in the fuel. If the sensors appear to be contaminated by silicon and all the silicon sealant is a non-silicon base, advise the customer to try a different fuel company. A missing fuel filler restrictor indicates the customer may have used leaded fuel.