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Oxygen Sensor O2S Heater Behind Catalytic Converter, Bank 1, Sensor 2, Checking

Observe all safety precautions: SAFETY PRECAUTIONS .

View clean working conditions: CLEAN WORKING CONDITIONS .

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

For wiring diagrams, component locations, and connector views, Refer to the appropriate System Wiring Diagram.

NOTE:

Oxygen Sensor (O2S) 1 Before Catalytic Converter Heater - Z29- is part of Oxygen Sensor (O2S) Before Three Way Catalytic Converter -G130- and cannot be replaced separately.

Special tools and workshop equipment required 

Test requirements 

Test procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK .

Start diagnosis 

-- Remove the engine covers. Refer to the appropriate Service Information.

Fig 1: Engine Cover -1- And -2-
GWWA10-11070Courtesy of AUDI OF AMERICA, LLC

-- Disconnect the oxygen sensor electrical harness connector. Oxygen sensor after three way catalytic converter - G130- / Oxygen Sensor O2S Behind Three Way Catalytic Converter Heater - Z29- -1-.

Fig 2: Identifying Heated Oxygen Sensor Connector
GWWA24-10869Courtesy of AUDI OF AMERICA, LLC

Checking internal resistance 

-- Using a Multimeter, check the Oxygen Sensor (O2S) 1 Before Catalytic Converter Heater - Z29- terminals 1 to 2 for resistance.

Specified value: 2.5 to 14.0 Ω (at Approx. 20° C).

If the specified value was Not obtained:

-- Replace the Oxygen sensor after three way catalytic converter - G130- / Oxygen Sensor O2S Behind Three Way Catalytic Converter Heater - Z29-. Refer to the appropriate Service Information.

-- Go to Final procedures.

If the specified value was obtained:

Checking voltage supply 

-- Switch the ignition ON.

-- Using a Multimeter, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- electrical harness connector terminal 1 to ground (GND) for voltage.

Specified value: Battery voltage.

-- Switch the ignition OFF.

If the specified value was Not obtained:

-- Check the Oxygen Sensor O2S Behind Three Way Catalytic Converter Heater - Z29- electrical harness connector T4l terminal 5 to Fuse SA17 in Fuse Panel A Connector or an open circuit, a short circuit to each other or Ground (GND).

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

-- Repair the circuit and replace any open fuses.

-- Go to Final procedures.

If the specified value was obtained:

Checking Ground (GND) activation 

-- Remove the Engine Control Module -J623-. Refer to the appropriate Service Information.

-- Using a Multimeter, check the Oxygen Sensor O2S Behind Three Way Catalytic Converter Heater - Z29- electrical harness connector to the Engine Control Module -J623- electrical harness connector T94 for resistance.

Oxygen sensor after three way catalytic converter - G130- / Oxygen Sensor O2S Behind Three Way Catalytic Converter Heater - Z29- electrical harness connector T4l terminal: Engine Control Module -J623- electrical connector T94 terminal:
2 46

Specified value: 1.5 Ω max.

If the specified value was Not obtained:

-- Check the wiring for a open circuit or short to Ground (GND).

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- Go to Final procedures.

If the specified value was obtained:

If no malfunction is detected in the wiring and if the voltage supply was OK:

-- Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .

-- Perform a road test to verify repair.

If the DTC does not return:

Generate readiness code. Refer to READINESS CODE .

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

-- Replace the Engine Control Module -J623-. Refer to the appropriate Service Information.

Final procedures 

-- Reinstall the engine covers, if necessary. Refer to the appropriate Service Information.

-- For connector location, removal and installation procedures. Refer to the appropriate Service Information.

-- After the repair work, the following work steps must be performed in the following sequence:

  1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
  2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
  3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .