10 Oxygen Sensor Ahead of TWC, Bank 1 - Interruption of Signal

P0134

10 Oxygen Sensor Ahead of TWC, Bank 1 - Interruption of Signal

Function
To diagnose the readiness for operation of the oxygen sensors, the position of the sensor voltage is evaluated (diagnosis is disabled in the case of certain faults or conditions).

Diagnosis conditions

P0134:

NOTE: The fault is stored after 2 minutes.

Wiring Diagram







Diagnosis Procedure

Part 1:

Part 2:

1 Check wiring harness.
1. Remove oxygen sensor connector 1 ahead of TWC.
2. Switch on the ignition.
3. Connect voltmeter to pins 3 and 4 of oxygen sensor connector 1 ahead of TWC towards the DME control module.

Display: approx. 450 mV

4. Start engine and run at high speed for 3 minutes.
5. Connect voltmeter to pin 1 and pin 2 of connector towards DME control module.

Display: battery voltage

If the measurement according to items 3 and 5 does not show the specified values, remove DME control module connector and check wiring for continuity.

If no continuity can be detected, repair wiring harness. If continuity exists, replace DME control module.

2 Check function of oxygen sensor.
1. Heat the oxygen sensors (road test car under load or run engine without load at high rpm).
2. Connect Porsche System Tester 2 or scan tool and read voltage of oxygen sensor 1 ahead of TWC.

Display: Voltage fluctuations between 100 mV and 800 mV
- Oxygen sensor OK.

3. Measure internal resistance.

Display: < 20 k ohms

3 Check oxygen sensor heating.
1. Remove oxygen sensor connector 1 ahead of TWC.
2. Connect ohmmeter to pins 1 and 2 of the oxygen sensor connector towards the oxygen sensor.

Display: 1.0 - 2.6 ohms at 25 °C.

3. Connect ohmmeter to pin 1 of the oxygen sensor connector towards the oxygen sensor and the oxygen sensor housing.

Display: infinity ohms

4. Connect ohmmeter to pin 2 of the oxygen sensor connector towards the oxygen sensor and the oxygen sensor housing.

Display: infinity ohms