Oxygen Sensor Relay: Testing and Inspection
SENSOR HEATEROxygen Sensor Heater Check:
1. Disconnect sensor wiring harness.
2. Connect an ohmmeter across terminals "B" and "C" on sensor side.
3. Meter should show continuity. If not, replace sensor.
RELAY
Oxygen Sensor Relay Testing:
1. Check that a "click" is heard at the relay when ignition is switched "ON" and "OFF." (Relay is located in the left front corner of the engine compartment.)
2. Remove relay and check that continuity does not exist across terminals "C" and "D."
3. Apply 12V and a ground to terminals "A" and "B." Check that continuity exists across terminals "C" and "D."
4. If not as specified, replace relay.