CO-Potentiometer reverse communication (SOP) is a resistive voltage divider, with the included consistently resistor and a potentiometer between the input contact controller and ground. The DIS is set to the engine compartment on the wall of the air flow units (see photo 1) and serves to adjusting the content of carbon monoxide (CO) in the exhaust gases.
The higher the voltage on the signal contact of the SOP, the lower level WITH the exhaust the gases. The controller detects an error STRs if control the voltage is outside the specified value (1-5V.) and stores in RAM respectively "27" or "28" WITH error code-potentiometer, which can be read in the diagnostic mode. In the presence of data error lamp is lit The "CHECK ENGINE" and most often indicates open circuit SOP. In this case, the controller does not takes into account the signal SOP and switches to control the motor according to the averaged values. Symptoms of malfunction of the circuit can be increased fuel consumption, the reduction in vehicle dynamics and unstable operation of the engine at idle.
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