Warning! The sensor is installed near the catalytic converter, which heats up to a high temperature when the engine is running. To avoid burns, check the oxygen concentration sensor and remove it after the engine has cooled down to a safe temperature. Before performing work, read the precautions for repairing the engine management system (see "Precautions when repairing the engine management system").
To complete the work you will need:
- multimeter (in voltmeter mode);
- inspection pit or overpass (for engines 2111 and 2112).
Examination
1. Prepare the car for work (see "Preparing the car for maintenance and repair"). Cars with engines 2111 and 2112 we install it on an inspection pit or overpass (see "Preparing the car for maintenance and repair").
2. Disconnect the wiring harness connector from the oxygen concentration sensor connector.
3. Connect the negative probe of the voltmeter to the engine ground. Turn on the ignition and check the supply voltage of the heating element at terminal B (the terminal designations are marked on the wiring harness block).
Note: The voltage at the terminal must be at least 12 V. If the voltage does not reach the connector or is less than 12 V, the battery is discharged, the power supply circuit is faulty, or the ECU is faulty.
4. Having connected the "minus" probe of the voltmeter to terminal C, we measure the voltage between terminals A and C.
Note: The voltage at the terminals should be 0.45 V. If the voltage does not reach the connector or it differs by more than 0.02 V, then the power supply circuit is faulty or the ECU is faulty.
Removal
1. Release the oxygen concentration sensor wire holder.
2. Key at 22 mm:
- on engines 21114 and 21124 we unscrew the sensor from the exhaust manifold and remove the sensor (shown with intake manifold removed);
- on engines 2111 and 2112 we unscrew the sensor from the inlet pipe and remove it.
Advice: You can verify that the sensor is faulty by replacing it with a known good one.
Installation
We install the sensor in the reverse order.