P0132

Wiring Diagram:

Circuit Description
The Heated Oxygen Sensor (HO2S) produces a voltage that varies between 100 mV and 900 mV under normal operating conditions. The powertrain control module (PCM) monitors this voltage and determines if the exhaust is lean or rich. If the voltage input at the PCM is about 100 mV the exhaust is lean, and if the voltage input is about 900 mV the exhaust is rich. The PCM constantly monitors the HO2S signal during closed loop operation and compensates for a rich or lean condition by decreasing or increasing fuel injector pulse width as necessary. If the HO2S 1 voltage remains excessively high for an extended period of time, DTC P0132 will be set.

Conditions for Running the DTC
^ Vehicle speed above 32 km/h (20 mph).
^ Engine rpm greater than 2000 RPM.
^ In closed loop for 20 seconds.
^ Barometric pressure greater than 75 kPa.

Conditions for Setting the DTC
^ Minimum voltage is greater than 300 mV.
^ Maximum voltage average greater than 950 mV and minimum voltage average greater than 400 mV.

Action Taken When the DTC Sets
^ The PCM illuminates the malfunction indicator lamp (MIL) after two consecutive ignition cycles in which the diagnostic runs with the fault active.
^ The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Freeze Frame buffer.

Conditions for Clearing the MIL/DTC
^ The MIL turns OFF after three consecutively passing trips without a fault present.
^ A History DTC clears after 40 consecutive warm-up cycles without a fault.
^ Use the scan tool Clear DTC Information function or disconnect the PCM battery feed in order to clear the DTC.

Diagnostic Aids
Check for any of the following conditions:
^ If any DTCs other than Fuel Trim (P0171 P0172), Misfire (P0300 to P0304), EGR (P0400) and HO2S 1 (P0131 to P0134) are set, diagnosis those DTCs first.
^ Before replacement of the HO2S, check the HO2S ground circuit for a possible open or short.
^ Fuel Pressure. The system will go rich if the fuel pressure is too high and a DTC P0132 may be set.
^ Check the EVAP Canister for fuel saturation.
^ Check for a leaking fuel pressure regulator diaphragm by checking the vacuum line to the fuel pressure regulator for the presence of fuel.
^ A shorted Heated Oxygen Sensor (HO2S). If the HO2S is internally shorted to voltage the HO2S reading displayed on the scan tool will be over 1 volt. Water contamination of the HO2S can cause a high HO2S voltage to be indicated. Note if the DTC P0132 occurs when driving through standing water or when operating the vehicle in wet driving conditions. Replace the HO2S if it is adversely affected by moisture.

An intermittent malfunction may be caused by a problem in the HO2S 1 sensor electrical circuit. Inspect the wiring harness and components for any of the following conditions:
^ Backed out terminals.
^ Improper mating of terminals.
^ Broken electrical connector locks.
^ Improperly formed or damaged terminals.
^ Faulty terminal to wire connections.
^ Physical damage to the wiring harness.
^ A broken wire inside the insulation.
^ Corrosion of electrical connections, splices, or terminals.

If the DTC P0132 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.

Test Description
The numbers below refer to the step numbers in the Diagnostic Table.
1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. This step will determine if fault is present. The vehicle must be at operating temperature.
3. Review Freeze Frame data to determine when the DTC set. Always record this information.