Oxygen Sensor Heating After TWC, Bank 2 - Open Circuit

P1118

Oxygen Sensor Heating After TWC, Bank 2 - Open Circuit

Function
The heated oxygen sensor generates a current signal, starting at approx. 300 °C, which provides information about the fuel/air mixture. This signal is used for the regulation of fuel injection. The oxygen sensor is heated to bring it quickly to operating temperature in order to start oxygen sensing earlier.

Diagnosis conditions

P1118:

Wiring Diagram







Diagnosis Procedure

Above limit







Below limit







Open circuit







Signal implausible







1 Check resistance of oxygen sensor heating.
1. Remove connector of oxygen sensor 2 after TWC.
2. Connect ohmmeter to pin 1 and pin 2 of the oxygen sensor connector towards the oxygen sensor.
Display: less then 2.6 ohm at 25 °C

2 Perform adaptation.
1. Switch on the ignition.
2. Wait one minute.
Do not press the accelerator.

3. Switch off the ignition for at least 10 seconds.
4. Read out the fault memory.

3 Measure resistance between oxygen sensor housing and oxygen sensor heating.
1. Remove connector of oxygen sensor 2 after TWC.
2. Connect ohmmeter to pin 1 of oxygen sensor housing and oxygen sensor connector towards the oxygen sensor.
Display: infinity ohms

3. Connect ohmmeter to pin 2 of oxygen sensor housing and oxygen sensor connector towards the oxygen sensor.
Display: infinity ohms