Heated Oxygen Sensor And Oxygen Sensor Regulation Before Catalytic Converter, Checking
Heated Oxygen Sensor
The following procedure is used to diagnose Heated Oxygen Sensor (HO2S) -G39- which is controlled by the Motronic Engine Control Module (ECM) -J623-.
Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Heated Oxygen Sensor (HO2S) -G39-.
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Motronic Engine Control Module (ECM) -J623- fuses OK.
- The Oxygen Sensor (O2S) Heater -Z19- before catalytic converter OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Exhaust system between catalytic converter and cylinder head properly sealed.
- Coolant Temperature at least 80° C.
Function test
-- Perform the function test located in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If specified values are obtained:
-- End diagnosis and switch the ignition off.
If the specified values are not obtained:
Procedure
-- Raise the vehicle..
-- Loosen the quick release fasteners -1- and -2- and remove the noise insulation panel.
-- Disconnect the black Heated Oxygen Sensor (HO2S) -G39- electrical harness connector -1-.
Checking primary voltage
-- Crank the engine.
-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) -G39- electrical harness connector terminals 2 to 6 for voltage.
Specified value: 0.400 to 0.500 Volts
-- Switch the ignition off.
If the specified value was not obtained:
-- Replace Heated Oxygen Sensor (HO2S) -G39-. Refer to Heated Oxygen Sensors before Catalytic Converter .
If the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
-- Install the test box. Refer to Wiring and Components, Checking with Test Box VAG 1598/42 .
If the manufacturers test box is not being used. Perform the following step.
-- Remove the Motronic Engine Control Module (ECM) -J623-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
-- Using a Multimeter --, check the Heated Oxygen Sensor (HO2S) -G39- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J623- electrical harness connector T94a terminals for an open circuit.
| Heated Oxygen Sensor (HO2S) -G39- electrical harness connector terminals | Motronic Engine Control Module (ECM) -J623- electrical connector T94a terminals or test box sockets |
|---|---|
| 1 | 60 |
| 2 | 61 |
| 5 | 81 |
| 6 | 82 |
Specified value: 1.5 Ω 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 found in the wiring:
-- Replace the Motronic Engine Control Module (ECM) -J623-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
Assembly is performed in the reverse order of removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
-- End of diagnosis.
Heated Oxygen Sensor 2
The following procedure is used to diagnose Heated Oxygen Sensor (HO2S) 2 -G108- which is controlled by the Motronic Engine Control Module (ECM) -J623-.
Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Heated Oxygen Sensor (HO2S) 2 -G108-.
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Motronic Engine Control Module (ECM) -J623- fuses OK.
- The Oxygen Sensor (O2S) 2 Heater -Z28- before catalytic converter OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Exhaust system between catalytic converter and cylinder head properly sealed.
- Coolant Temperature at least 80° C.
Function test
-- Perform the function test located in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If specified values are obtained:
-- End diagnosis and switch the ignition off.
If the specified values are not obtained:
Procedure
-- Raise the vehicle..
-- Loosen the quick release fasteners -1- and -2- and remove the noise insulation panel.
-- Remove the screws -arrows- and the oxygen sensor electrical harness connector heat shield.
-- Disconnect the black Heated Oxygen Sensor (HO2S) 2 -G108- electrical harness connector -5-.
Checking primary voltage
-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) 2 -G108- electrical harness connector terminals 2 to 6 for voltage.
Specified value: 0.400 to 0.500 Volts
-- Switch the ignition off.
If the specified value was not obtained:
-- Replace the Heated Oxygen Sensor (HO2S) 2 -G108-. Refer to Heated Oxygen Sensors before Catalytic Converter .
If the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
-- Install the test box. Refer to Wiring and Components, Checking with Test Box VAG 1598/42 .
If the manufacturers test box is not being used. Perform the following step.
-- Remove the Motronic Engine Control Module (ECM) -J623-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
-- Using a Multimeter --, check the Heated Oxygen Sensor (HO2S) 2 -G108- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J623- electrical harness connector T94a terminals for an open circuit.
| Heated Oxygen Sensor (HO2S) 2 -G108- electrical harness connector terminals | Motronic Engine Control Module (ECM) -J623- electrical connector T94a terminals or test box sockets |
|---|---|
| 1 | 59 |
| 2 | 84 |
| 5 | 83 |
| 6 | 62 |
Specified value: 1.5 Ω 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 found in the wiring:
-- Replace the Motronic Engine Control Module (ECM) -J623-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
Assembly is performed in the reverse order of removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
-- End of diagnosis.
Heated Oxygen Sensor 3
The following procedure is used to diagnose Heated Oxygen Sensor (HO2S) 3 -G285- which is controlled by the Engine Control Module (ECM) 2 -J624-.
Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Heated Oxygen Sensor (HO2S) 3 -G285-.
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Engine Control Module (ECM) 2 -J624- fuses OK.
- The Oxygen Sensor (O2S) 3 Heater -Z62- before catalytic converter OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Exhaust system between catalytic converter and cylinder head properly sealed.
- Coolant Temperature at least 80° C.
Function test
-- Perform the function test located in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If specified values are obtained:
-- End diagnosis and switch the ignition off.
If the specified values are not obtained:
Procedure
-- Raise the vehicle..
-- Loosen the quick release fasteners -1- and -2- and remove the noise insulation panel.
-- Disconnect the black Heated Oxygen Sensor (HO2S) 3 -G285- electrical harness connector -2-.
Checking primary voltage
-- Crank the engine.
-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) 3 -G285- electrical harness connector terminals 2 to 6 for voltage.
Specified value: 0.400 to 0.500 Volts
-- Switch the ignition off.
If the specified value was not obtained:
-- Replace Heated Oxygen Sensor (HO2S) 3 -G285-. Refer to Heated Oxygen Sensors before Catalytic Converter .
If the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
-- Install the test box. Refer to Wiring and Components, Checking with Test Box VAG 1598/42 .
If the manufacturers test box is not being used. Perform the following step.
-- Remove the Engine Control Module (ECM) 2 -J624-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
-- Using a Multimeter --, check the Heated Oxygen Sensor (HO2S) 3 -G285- electrical harness connector terminals to the Engine Control Module (ECM) 2 -J624- electrical harness connector T94b terminals for an open circuit.
| Heated Oxygen Sensor (HO2S) 3 -G285- electrical harness connector terminals | Engine Control Module (ECM) 2 -J624- electrical connector T94b terminals or test box sockets |
|---|---|
| 1 | 60 |
| 2 | 61 |
| 5 | 81 |
| 6 | 82 |
Specified value: 1.5 Ω 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 found in the wiring:
-- Replace the Engine Control Module (ECM) 2 -J624-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
Assembly is performed in the reverse order of removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
-- End of diagnosis.
Heated Oxygen Sensor 4
The following procedure is used to diagnose Heated Oxygen Sensor (HO2S) 4 -G286- which is controlled by the Engine Control Module (ECM) 2 -J624-.
Use only gold-plated terminals when servicing terminals in the electrical harness connectors of the Heated Oxygen Sensor (HO2S) 4 -G286-.
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test requirements
- The Engine Control Module (ECM) 2 -J624- fuses OK.
- TheOxygen Sensor (O2S) 4 Heater -Z63- before catalytic converter OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Exhaust system between catalytic converter and cylinder head properly sealed.
- Coolant Temperature at least 80° C.
Function test
-- Perform the function test located in diagnostic mode 06. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .
If specified values are obtained:
-- End diagnosis and switch the ignition off.
If the specified values are not obtained:
Procedure
-- Raise the vehicle..
-- Loosen the quick release fasteners -1- and -2- and remove the noise insulation panel.
-- Remove the screws -arrows- and the oxygen sensor electrical harness connector heat shield.
-- Disconnect the brown Heated Oxygen Sensor (HO2S) 4 -G286- electrical harness connector -4-.
Checking primary voltage
-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) 4 -G286- electrical harness connector terminals 2 to 6 for voltage.
Specified value: 0.400 to 0.500 Volts
-- Switch the ignition off.
If the specified value was not obtained:
-- Replace the Heated Oxygen Sensor (HO2S) 4 -G286-. Refer to Heated Oxygen Sensors before Catalytic Converter .
If the specified value was obtained:
Checking wiring
If the manufacturers test box is being used. Perform the following step.
-- Install the test box. Refer to Wiring and Components, Checking with Test Box VAG 1598/42 .
If the manufacturers test box is not being used. Perform the following step.
-- Remove the Engine Control Module (ECM) 2 -J624-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
-- Using a Multimeter --, check the Heated Oxygen Sensor (HO2S) 4 -G286- electrical harness connector terminals to the Engine Control Module (ECM) 2 -J624- electrical harness connector T94b terminals for an open circuit.
| Heated Oxygen Sensor (HO2S) 4 -G286- electrical harness connector terminals | Engine Control Module (ECM) 2 -J624- electrical connector T94b terminals or test box sockets |
|---|---|
| 1 | 59 |
| 2 | 84 |
| 5 | 83 |
| 6 | 62 |
Specified value: 1.5 Ω 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 found in the wiring:
-- Replace the Engine Control Module (ECM) 2 -J624-. Refer to ENGINE CONTROL MODULE, REMOVING AND INSTALLING .
Assembly is performed in the reverse order of removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
-- End of diagnosis.