DTC 11

CIRCUIT DIAGRAM





USING MULTI-USE TESTER





USING OSCILLOSCOPE

Steps 1-3:

HARNESS INSPECTION PROCEDURE


OPERATION

The Oxygen sensor is provided on the gathering area of the manifolds or the outlet of the turbocharger, using the principle of the oxygen concentration cell of the solid electrolytic material. The output Voltage has a characteristic to rapidly vary near the theoretical air-fuel mixture ratio.

This characteristic is used to detect the concentration of oxygen gas in the exhaust gas, and this is feed back to ECU to check whether the air-fuel mixture ratio is richer or leaner than the theoretical one.

This feed back system accurately controls the air-fuel mixture ratio to be the theoretical air-fuel mixture ratio which achieves the best clarification efficiency of the catalytic converter rhodium. Here, the Oxygen sensor is provided with the heater to allow feed back control of the air-fuel mixture ratio in a short time after the engine is started.


TROUBLESHOOTING HINTS

Even if the Oxygen sensor is troubled, the driveability is hardly influenced. Since the air-fuel mixture ratio shifts toward the rich side, the driveability becomes rather better. However. hazardous components (HC, CO, NOx) increase in the exhaust gas since the air-fuel mixture ratio is not feed back for the control.