P0132

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) supplies a bias voltage of about 450 mV between the HO2S high and low signal circuits. When measured with a 10 megaohm Digital Multimeter (DMM), this may display as low as 320 mV. The oxygen sensor varies the voltage within a range of about 1000 mV when the exhaust is rich, down through about 100 mV when exhaust is lean. The PCM constantly monitors the Heated Oxygen Sensor (HO2S) signal during closed loop operation and compensates for a rich or lean condition by decreasing or increasing injector pulse width as necessary. If the HO2S 1 voltage remains excessively high for an extended period of time, DTC P0132 will set.

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0410, P0440, P0442, P0443, P0446, P0449, P1441 are not set.
^ System voltage is greater than 9 volts.
^ Closed loop commanded air/fuel ratio is between 14.5 and 14.8.
^ Throttle angle is. between 3 percent and 40 percent.

CONDITIONS FOR SETTING THE DTC
The HO2S 1 signal voltage remains above 975 mV during normal closed loop operation for longer than 45 seconds.

OR

The HO2S 1 signal voltage remains above 200 mV during deceleration fuel mode operation for longer than 55 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ First failure:
- The MIL is not turned ON.
- A DTC is stored in memory under Failed Last Test.
- The Failure Records are stored.
^ Second consecutive drive cycle with a failure:
- The MIL is turned ON.
- A DTC is stored in memory under history.
- The Freeze Frame data is stored.
- The Failure Records are stored.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The control module turns OFF the malfunction indicator lamp (MIL) after the third consecutive trip the diagnostic has run and passed.
^ The history DTC will clear if the fault conditions have not been detected for 40 warm-up cycles.
^ A scan tool can be used to clear DTC information.

DIAGNOSTIC AIDS
Check the following items:
^ Fuel pressure: The system will go rich if pressure is too high. The PCM can compensate for some increase. However, if fuel pressure is too high, a DTC P0132 may be set.
Refer to Fuel System Diagnosis. Component Tests and General Diagnostics
^ Fuel injectors: Refer to Fuel Injector Coil Test. Component Tests and General Diagnostics
^ Check the EVAP Canister for fuel saturation. If the EVAP Canister is full of fuel, check the canister control and hoses. Refer to DTC P0440. P0440
^ Mass Air Flow (MAF) sensor: Disconnect the MAF sensor and see if the rich condition is corrected. If so, replace the MAF sensor. Refer to Mass Air Flow (MAF) Sensor Replacement.
^ Fuel pressure regulator: Check for a leaking fuel pressure regulator diaphragm by checking vacuum line to regulator for the presence of fuel. If a condition is found, replace the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement (VIN K) or Fuel Pressure Regulator Replacement (VIN 1).
^ TP sensor: An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine accelerating. Throttle Angle displayed on a scan tool should increase steadily from 0 percent to 100 percent when opening the throttle. If not, check the TP sensor for loose mounting screws. If the TP mounting screws are OK, replace the TP sensor. Refer to Throttle Position (TP) Sensor Replacement.
^ Shorted heated oxygen sensor (HO2S): If the HO2S is internally shorted the HO2S voltage displayed on the scan tool will be over 1 volt. Disconnect the affected HO2S and jumper the HO2S low circuit to ground with the ignition ON, and the engine OFF. If the displayed HO2S voltage changes from over 1000 mV to around 450 mV, replace the HO2S. Silicon contamination of the HO2S can also cause a high HO2S voltage to be indicated. This condition is indicated by a powdery white deposit on the portion of the HO2S exposed to the exhaust stream. If contamination is noticed, replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) 1 Replacement.
^ Open HO2S High or Low Signal Circuit or Malfunctioning HO2S: A poor connection or open in the HO2S high or low signal circuit can cause the DTC to set during deceleration fuel mode. An HO2S which is malfunctioning and not allowing a full voltage swing between the rich and lean thresholds can also cause this condition. Operate the vehicle while monitoring the HO2S voltage with a scan tool. If the HO2S voltage is limited within a range between 300 mV to 600 mV, check the HO2S high and low signal circuit wiring and associated terminal connections.
^ If the wiring and connections are OK, replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) 1 Replacement.

If the DTC cannot be duplicated and is determined to be intermittent, reviewing the Freeze Frame/Fail Records can be useful in determining when the DTC was last set. Also refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION

Steps 1-10:

The number below refers to the step number on the diagnostic table.
3. This DTC failing during deceleration fuel mode operation (vehicle speed above 40 km/h (25 mph). TP angle below 3 percent) may indicate a condition described in Diagnostic Aids. If this DTC test passes while the Freeze Frame/Failure Records conditions are being duplicated, an intermittent condition is indicated. Review the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.