Control Circuit Inspection

IG "OFF" & Disconnect HO2S(S2) connector.
IG "ON" & ENG "OFF".
Measure voltage between control terminal of HO2S(S2) heater harness connector and chassis ground.

Specification: Approx. 3.5V

Is the measured voltage within specification?
YES
- Go to COMPONENT INSPECTION procedure.
NO
- Repair or replace as necessary and then, go to VERIFICATION OF VEHICLE REPAIR procedure.