P0132

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) supplies a bias voltage of about 450 mV between the Heated Oxygen Sensor (HO2S) high signal and low signal circuits. When measured with a 10-megaohm 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 10 mV when exhaust is lean. The PCM constantly monitors the 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 time, DTC P0132 will be 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, or P1441 are not set.
^ The system voltage is more than 9 volts.
^ The closed loop commanded air/fuel ratio is between 14.5-14.8.
^ The throttle angle is between 3-40 percent.

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.
^ Use a scan tool in order to clear the MIL and the DTC.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
^ The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

DIAGNOSTIC AIDS
Check the following items:
^ The fuel pressure-The system will go rich if pressure is too high. The PCM can compensate for some increase. If fuel pressure is too high, a DTC P0132 may be set.
^ The fuel injectors-Refer to Fuel Injector Coil Test. Component Tests and General Diagnostics
^ Fuel saturation of the Evaporative Emissions (EVAP) canister-If the EVAP Canister is full of fuel, check the canister control and check the hoses. Refer to Evaporative Emission (EVAP) Control System Description.
^ The 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 Manifold Absolute Pressure (MAP) Sensor Replacement
^ The fuel pressure regulator-Check for a leaking fuel pressure regulator diaphragm by checking the vacuum line to the regulator for the presence of fuel. If a condition is found, replace the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement
^ The Throttle Position (TP) Sensor-An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine accelerating. The 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
^ A shorted heated Oxygen Sensor (HO2S)-Inspect for the following conditions and repair any conditions as needed:
- If the HO2S is internally-shorted, the HO2S voltage displayed on the scan tool will be more than 1 volt. Disconnect the affected HO2S and jumper the HO2S low signal circuit to ground with the key ON, and with the engine not running.
- If the displayed HO2S voltage changes from more than 1,000 mV to around 450 mV, replace the HO2S. Refer to Heated Oxygen Sensor (HO2S) 1 Replacement or Heated Oxygen Sensor (HO2S) 2 Replacement
- If the portion of the HO2S that is exposed to the exhaust stream is covered with a powdery white substance, silicon contamination is evident. This condition can cause a high HO2S voltage to be indicated. If you notice any contamination, replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) 1 Replacement, or to Heated Oxygen Sensor (HO2S) 2 Replacement
^ An open HO2S high or low signal circuit, or a malfunctioning HO2S-Inspect for the following conditions and repair any conditions as needed:
- A poor connection or open in the HO2S high or low signal circuit may cause the DTC to set during deceleration fuel mode. Use a corresponding mating terminal in order to check for proper terminal tension. Refer to Wiring Repairs in Diagrams.
- A low signal circuit in the HO2S signal may cause the DTC to set during deceleration fuel mode. If the HO2S voltage is limited within a range between 300-600 mV, check the HO2S signal, the low circuit wiring, and the associated terminal connections. Refer to Heated Oxygen Sensor (HO2S) Wiring Repairs in Diagrams.
- An HO2S which is malfunctioning and not allowing a full voltage swing between the rich and lean thresholds may cause this condition. Operate the vehicle while monitoring the HO2S voltage with a scan tool.
^ If the wiring and the connections are OK, replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) 1 Replacement, or to Heated Oxygen Sensor (HO2S) 2 Replacement

TEST DESCRIPTION

Steps 1-10:

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