Oxygen Sensor Relay: Testing and Inspection

INSPECTION




1. REMOVE RELAY BOX COVER
2. REMOVE A/F SENSOR HEATER RELAY (Marking: A/F)
3. INSPECT A/F SENSOR HEATER RELAY




a. Inspect the relay continuity.
1. Using an ohmmeter, check that there is continuity between terminals 1 and 2.

If there is no continuity, replace the relay.

2. Check that there is no continuity between terminals 3 and 5.

If there is continuity, replace the relay.




b. Inspect the relay operation.
1. Apply battery positive voltage to terminals 1 and 2.
2. Using an ohmmeter, check that there is continuity between terminals 3 and 5.

If there is no continuity, replace the relay.

4. REINSTALL A/F SENSOR HEATER RELAY
5. REINSTALL RELAY BOX COVER