Oxygen Sensor (O2S) 1 (Behind Three Way Catalytic Converter (TWC)) Heater Z29 , Checking
Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 , Checking
NOTE:
- Vehicle must be raised before electrical harness connector for the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 is accessible.
- When servicing terminals in harness connector of Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 , use only gold-plated terminals.
Special tools, testers and auxiliary items required
- Multimeter.
- Wiring diagram.
Test requirements
- The Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 fuse OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Ignition switched off.
Test sequence
- Remove the right vehicle floor cover - arrows -.
Checking internal resistance
- Disconnect the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 electrical harness connector - 2 -.
- Using a multimeter, check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 electrical harness connector terminals 1 to 2 for resistance.
Specified value: 1.0 to 20.0 Ohms (at approx. 20 degrees C)
If the specification was not obtained:
- Replace the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29.
If the specification was obtained:
Checking voltage supply
- Using a multimeter , check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 electrical harness connector terminal 1 to Fuel Pump Relay J17 terminal 2 for an open circuit.
Oxygen Sensor (O2S) 1 (behind Three Fuel Pump Relay J17
Way Catalytic Converter (TWC)) Heater electrical harness
Z29 electrical harness connector connector terminal
terminal
1 2
- Turn key on:
Specified value: 12.5 Battery voltage.
If the specification was not obtained:
- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the faulty wiring connection.
- Turn key off.
If the specification was obtained:
Checking Ground (GND) activation
If the manufacturers test box is being used. Perform the following step.
- Install the test box.
If the manufacturers test box is not being used. Perform the following step.
- Remove the Motronic Engine Control Module (ECM) J220.
- Using a multimeter , check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater Z29 electrical harness connector terminal 2 to the Motronic Engine Control Module (ECM) J220 electrical harness connector terminal 63 for an open circuit according to the wiring diagram.
Oxygen Sensor (O2S) 1 (behind Three Motronic Engine Control
Way Catalytic Converter (TWC)) Heater Module (ECM) J220 electrical
Z29 electrical harness connector connector test box socket
terminal
2 63
Specified value: 1.5 Ohms max.
If the specification was not obtained:
- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the faulty wiring connection.
If no malfunction is detected in the wiring and if the voltage supply was OK:
- Replace the Motronic Engine Control Module (ECM) J220.
- Install the right vehicle floor cover.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. If necessary, erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. If the DTC memory was erased, generate readiness code.
- End of diagnosis.