Oxygen Sensor Light
- Turn cancel switch located under the steering column on. See Fig 1 . Without starting engine, turn ignition on. check that sensor light is on but not flashing. If sensor light does not light, first check that bulb is good or that there is not a loose connection.
- Once the sensor light is confirmed operational and is on, start engine and warm to normal operating temperature. Run engine speed up to 1500-2000 RPM, checking that sensor light flashes. If not, check O2 sensor, mixture control solenoid valve, idle mixture, thermal switch loose connectors, defective carburetor, defective microswitches or defective ECM unit. If system tests satisfactory, be sure to turn cancel switch and ignition off.