Vauxhall Workshop Service and Repair Manuals

DTC P0135 - LPL or LPV

Diagnostic Instructions

DTC Descriptor

Diagnostic Fault Information

Circuit/System Description

The heated oxygen sensor (HO2S) heater reduces the time required for the oxygen sensor to reach operating temperature and maintains the operating temperature during extended idle periods. When the ignition is turned to the ON position, ignition voltage is supplied directly to the sensor heater. The engine control module (ECM) controls the heater operation by first modulating the control circuit to ground when the sensors are cold. This prevents the possibility of thermal shock to the sensor, from condensation build-up on the sensor, by controlling the sensors rate of heating. After a predetermined amount of time, the ECM commands the heaters ON continuously. Once the sensor reaches operating temperature, the ECM may modulate the heater control circuit to ground, to maintain a desired temperature.

The ECM controls the heater by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.

Conditions for Running the DTC

Conditions for Setting the DTC

The ECM detects an open, a short to ground, or a short to voltage in the heater circuits of the HO2S when the heater is commanded ON.

Action Taken When the DTC Sets

DTC P0135 is a Type B DTC.

Conditions for Clearing the DTC

DTC P0135 is a Type B DTC.

Diagnostic Aids

Reference Information

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

Circuit/System Verification

1. Engine idling at operating temperature for at least 30 s. Observe the DTC information, DTCs P0030, P0031 or P0032 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B52 Heated Oxygen Sensor.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 2 and ground.

Note:  The ignition circuit supplies voltage to other components. Make sure you test all circuits for a short to ground or test all components for being shorted that share the ignition circuit.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all the components connected to the ignition circuit and replace as necessary.

3. Connect a test lamp between the heater control circuit terminal 1 and B+. The test lamp should not illuminate.

⇒	If the test lamp is always ON, test the control circuit for a short to ground. If the circuit test normal, replace the K20 Engine Control Module.

4. Idle the engine, and verify the test lamp illuminates or flashes.

⇒	If the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit/connections test normal, replace the K20 Engine Control Module.

5. If all circuits/connections test normal, test or replace the B52 Heated Oxygen Sensor.

Component Testing

Static Test

1. Ignition OFF, disconnect the harness connector at the B52 Heated Oxygen Sensor.
2. Test the B52 Heated Oxygen Sensor resistance for 1.5-10 Ω.

⇒	If not within the specified range, replace the B52 Heated Oxygen Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.