Cruze

DTC P0136

The heated oxygen sensor (HO2S) 2 circuit diagnostics monitors the voltage on the signal circuit of the post catalyst oxygen sensor. In order to control emissions of hydrocarbons, carbon monoxide (CO), and oxides of nitrogen (NOX), a 3-way catalytic converter is used. The catalyst within the converter promotes a chemical reaction which oxidises the hydrocarbons and CO present in the exhaust gas, converting the hydrocarbons and the CO into harmless water vapour and carbon dioxide. The catalyst also reduces the NOx , converting the NOx into nitrogen. The engine control module (ECM) has the ability to monitor this process using the heated oxygen sensors HO2S 1 and heated oxygen sensor (HO2S) 2. The heated oxygen sensor (HO2S) 1 produces an output signal which indicates the amount of oxygen present in the exhaust gas entering the 3-way catalytic converter. The heated oxygen sensor (HO2S) 2 produces an output signal which indicates the oxygen storage capacity of the catalyst. This in turn indicates the catalysts ability to convert exhaust gases efficiently. If the catalyst is operating efficiently, the heated oxygen sensor (HO2S) 1 signal will be far more active than that produced by the heated oxygen sensor (HO2S) 2.

The HO2S utilises the following circuits:

P0136 00

P0136 00

DTCs P0136 00 is a Type B DTCs.

DTCs P0136 00 is a Type B DTCs.

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.

Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the B52B Heated Oxygen Sensor 2.
2. Ignition OFF, measure for less than 5 Ω between the B52B Heated Oxygen Sensor 2 low signal circuit terminal 4 and ground.

⇒	If more than the specified range, test the appropriate HO2S low signal circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

3. Ignition ON, verify the appropriate scan tool HO2S parameter is approximately 450 mV.

⇒	If more than the specified value, test the appropriate B52B Heated Oxygen Sensor 2 high signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If less than the specified value, test the appropriate B52B Heated Oxygen Sensor 2 high signal circuit terminal 2 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 B52B Heated Oxygen Sensor 2 high signal circuit terminal 2. Toggle the jumper wire between the B52B Heated Oxygen Sensor 2 low signal circuit terminal 4 and battery voltage. Verify the appropriate scan tool HO2S 2 parameter toggles between 0 mV and approximately 1000 mV.

⇒	If the appropriate scan tool B52B Heated Oxygen Sensor 2 parameter does not toggle correctly, test the B52B Heated Oxygen Sensor 2 high signal circuit terminal 2 for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

5. If all circuits test normal, replace the appropriate B52B Heated Oxygen Sensor 2.

Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution in the Preface section.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.