Control Circuit Inspection

■ Check voltage 

1. IG "OFF". Disconnect HO2S connector.
2. IG "ON".
3. Measure voltage between Heater Control terminal of the HO2S harness connector and chassis ground.

   Specification:  2~3V

4. Is voltage within the specification?

   YES 

   • Go to "Component Inspection " procedure.

   NO 

   • Repair as necessary and go to "Verification of Vehicle Repair " procedure.
   NOTE: HO2S must have a clean air reference to function properly. The air is obtained by way of the sensor wire (s). Do not attempt to repair the wire (s), connector, or the terminals.