Cruze

DTC P0134

The wide band heated oxygen sensor (HO2S) measures the amount of oxygen in the exhaust stream more quickly and accurately than the switching style HO2S. The wide band sensor consists of an oxygen sensing cell, an oxygen pumping cell, and a heater. The exhaust gas sample passes through a diffusion gap between the sensing cell and the pumping cell. The engine control module (ECM) supplies a signal voltage to the HO2S and uses this voltage as a reference to the amount of oxygen in the exhaust system. An electronic circuit within the ECM controls the pump current through the oxygen pumping cell in order to maintain a constant signal voltage. The ECM monitors the voltage variation on the signal circuit and attempts to keep the voltage constant by increasing or decreasing the amount of current flow or reversing the direction of the current flow to the pumping cell. By measuring the direction and amount of current required to maintain the signal voltage, the ECM can determine the concentration of oxygen in the exhaust. The signal voltage is displayed as a lambda value. A lambda value of 1 is equal to a stoichiometric air fuel ratio of 60:1. Under normal operating conditions, the lambda value will remain around 1. When the system is lean, the oxygen level will be high and the lambda value will be high, or more than 1. When the system is rich, the oxygen level is low and the lambda value will be low, or less than 1. The ECM uses this information to maintain the proper air/fuel ratio.

DTC P0134 is a Type C DTC.

DTC P0134 is a Type C DTC.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Clear the DTCs with a scan tool.
2. Operate the vehicle within the conditions for running and setting the DTC. The DTC should not set.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Note: All modules must be powered down or misdiagnosis may result.

1. Ignition OFF, disconnect the scan tool and wait 60 s to ensure all modules are powered down.
2. Disconnect the harness connector at the B52A Heated Oxygen Sensor.
3. Ignition ON, verify the scan tool HO2S parameter is approximately 450 mV.

⇒	If more than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

4. Ignition ON, install a 3 A fused jumper wire at the B52 Heated Oxygen Sensor high signal circuit terminal 3. Toggle the jumper wire between the B52 Heated Oxygen Sensor low signal circuit terminal 4 and the battery voltage and also between the B52 Heated Oxygen Sensor low signal circuit terminal 3 and ground. Verify the appropriate scan tool HO2S parameter toggles between 0 mV and approximately 1 000 mV.

⇒	If the appropriate scan tool HO2S parameter does not toggle correctly, test the HO2S high signal circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

5. If all circuits test normal, replace the B52 Heated Sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.